# SNOMED CT Document Library The SNOMED CT Document Library is a centralized resource offering access to a wide range of official SNOMED CT materials, including Specifications, Implementation Guides, Practical Guides, and User Guides. It is designed to support implementers, developers, and other stakeholders in understanding and applying SNOMED CT effectively in real-world scenarios.
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PRACTICAL GUIDES​E.g. Starter Guide, Data Analytics Guide, Reference Set Practical Guide, Terminology Services Guide/files/pjayhATCUOGCwSF2VceR
SPECIFICATIONSE.g. Release File Specification, Expression Constraint Language Specification/files/Ow7JLl1caV5w3xyXjwkK
IMPLEMENTATION GUIDES​E.g., LOINC Ontology, Nutrition Care Process Terminology, Cancer Synoptic Reporting/files/vn4lNxtVzRpSVBCuoiBn
USER GUIDES​E.g., Browser User Guide, Snap2SNOMED User Guide/files/o0uINcDFyNuHhWm8fP79
*** ## Document Index
SNOMED CT DocumentLink
Allergy Implementation Guide/spaces/EUp9nJwjJLZYACbE3UwO
Authoring Platform User Guide/spaces/O8kNzHFIgz2UFgwrcB08/pages/fN0ZTayKgtcniT7oMtyk
Browser Guide/spaces/1kHdBxHtH99oJ85gNaa3
Cancer Synoptic Reporting Implementation Guide/spaces/iVNO851qfehALjJyjfuh
Clinical Decision Support Guide/spaces/XxY5vKuPdiVBdqbdZl1x
Compositional Grammar Specification/spaces/VgpC90r7t9DyATri97GG
Content Request Service Guide/spaces/T7gOK7qF5jKUT64ZHaBu/pages/utTT9sgHrLKi6YglSMFa
Context Representation Implementation Guide/spaces/NsUpoYYIwAXcVvsqbyLS
Data Analytics Guide/spaces/uKngFry3XF9A8phdXFe8
Diagramming Specification/spaces/M5YwUfVkVdFLDT6IXbBg
Editorial Guide/spaces/uoSxuN6wQMDYcvuq2wNX
EDQM to SNOMED CT Dose Form Map Guide/spaces/UBtt8xnBO4xFyq2mN9lM/pages/qJOfLBXfoqHRijBbQkRl
EHR Requirements Guide/spaces/2zGgKVo3oaP8h8IA9Bfu
Expression Constraint Language Specification/spaces/sOJBD7YbxAy9bD1Ko9L9
Extension Guide/spaces/3RKZIWpWFT0ocCgNT16E
Glossary/spaces/P21QucCX9Y41nBQt50ad
Governance and Advisory Handbook/spaces/o42BW7myfdY0cCA3n9z9
GPS Implementation Guide/spaces/839ZLPSqBl8VA0IuWNe3
Guide for COVID-19/spaces/KjTEXok2qo0NibxpfDHl
Guía de Introducción a SNOMED CT/spaces/6qRORWNoEtGGQyEdx8kp
Guía del Centro Nacional de Referencia (CNR)/spaces/I7N0Q2Su8RGW5pAlIrWt
ICD-10 Map Specification/spaces/WdB6Is6LaDpXsfaSDN39
Implementation Fact Sheets/spaces/oTI6NZy7x0aaiM5aXOsc
Implementation Maturity Framework/spaces/AgzcOCN6Pv1YKOlOoAdf
Intro a SCT para proveedores/spaces/gJUdYtsAnX415FsKishB
IPS Implementation Guide/spaces/VnsfKeI5MuCXZbpiAQnu
LOINC Ontology Implementation Guide/spaces/vdInPDnQhewgUCH6BOCp
Logical Profile Specification/spaces/hRUJsLa2ant5L63pkp1O
Machine-Readable Concept Model/spaces/wLJPOzgAQsSAYr6nhvCl
Mapping Guide/spaces/vfZ2h198vJ4VJyfraIHQ
MLDS User Guide/spaces/LYgfgtQAEX6IwigniPM1
NCPT Implementation Guide/spaces/I4wWbsWWSniTcRzkLBwE
National Release Center Guide/spaces/P1frmzZuNvoHsCrG7SKQ
OWL Reference Set Specification/spaces/UVgNFMSypqSsi48DpFEe
Postcoordination Guide/spaces/usjN9isxKh4cLDTFopLg
Reference Set Guide/spaces/qOI2v58ZsXOoklmwBOk4
Release File Specification/spaces/irKbJsZG57nSWZA4GT0M
Search and Data Entry Guide/spaces/CEAcChvWjWEu16YmwNrz
Simplex User Guide/spaces/WOqw6Pr88mt7eMEp8PEV
Snap2SNOMED User Guide/spaces/hhAMcxzclQGXKlrJY7Lj
SQL Practical Guide/spaces/LnTo62BQeQSW6tBNKv0T
Starter Guide/spaces/UmSUeu96fIQZWDm7RISx
Translation Guide/spaces/RqD57MbRYSFSsKbOrkOa
Translation Management Guide/spaces/LWaBsNxFVew6RgxiYZZQ
Template Syntax Specification/spaces/zMLFwMoInWP79jP2Up2p
Terminology Services Guide/spaces/t4wRQcj6gyQPunraJrP0
URI Standard/spaces/kgrE9Yh9vMDqL5ThuXjH
Vendor Introduction Guide/spaces/QoBkzGO8Ufkm7izM5BB1
*** {% hint style="info" %} © Copyright 2026 International Health Terminology Standards Development Organisation, all rights reserved. This document is a publication of International Health Terminology Standards Development Organisation, trading as SNOMED International. SNOMED International owns and maintains SNOMED CT®. Any modification of this document (including without limitation the removal or modification of this notice) is prohibited without the express written permission of SNOMED International. This document may be subject to updates. Always use the latest version of this document published by SNOMED International. This can be viewed online and downloaded by following the links on the front page or cover of this document. SNOMED®, SNOMED CT® and IHTSDO® are registered trademarks of International Health Terminology Standards Development Organisation. SNOMED CT® licensing information is available at . For more information about SNOMED International and SNOMED International Membership, please refer to [http://www.snomed.org](http://www.ihtsdo.org/) or contact us at [info@snomed.org](mailto:info@ihtsdo.org). {% endhint %} # SNOMED CT Glossary ## Introduction The purpose of this document is to serve as a comprehensive glossary of terms and phrases commonly employed within the SNOMED CT community. As an international standard for health terminology, SNOMED CT is utilized by a diverse group of professionals, including clinicians, researchers, and developers, each of whom may encounter unique terms and concepts. This glossary aims to provide clear, precise definitions and explanations, facilitating a deeper understanding and more effective communication among users. Whether you are new to SNOMED CT or an experienced member seeking to refine your knowledge, this resource will assist you in navigating the complex landscape of health terminology. By demystifying the terminology and concepts associated with SNOMED CT, this glossary helps ensure that users can more effectively engage with the system, fostering collaboration and innovation across the global healthcare community. {% hint style="info" %} © Copyright 2026 International Health Terminology Standards Development Organisation, all rights reserved. This document is a publication of International Health Terminology Standards Development Organisation, trading as SNOMED International. SNOMED International owns and maintains SNOMED CT®. Any modification of this document (including without limitation the removal or modification of this notice) is prohibited without the express written permission of SNOMED International. This document may be subject to updates. Always use the latest version of this document published by SNOMED International. This can be viewed online and downloaded by following the links on the front page or cover of this document. SNOMED®, SNOMED CT® and IHTSDO® are registered trademarks of International Health Terminology Standards Development Organisation. SNOMED CT® licensing information is available at . For more information about SNOMED International and SNOMED International Membership, please refer to [http://www.snomed.org](http://www.ihtsdo.org/) or contact us at [info@snomed.org](mailto:info@ihtsdo.org). {% endhint %} Provide Feedback # A Provide Feedback # abnf ## ABNF **This is an abbreviation for Augmented Backus-Naur Form.** ## Augmented Backus-Naur Form A language used to define the formal syntax of another language in computer science. #### Notes * *Augmented Backus-Naur Form* is: ``` * used to define syntax for Internet specifications. ``` ``` * defined by Internet Standard 68, RFC 5234. ``` ## Alternatives * ABNF ## Related Links * Internet Engineering Task Force * [Augmented BNF for Syntax Specifications](https://tools.ietf.org/html/rfc5234) * Wikipedia * [Augmented Backus-Naur form](https://en.wikipedia.org/wiki/Augmented_Backus%E2%80%93Naur_form) Provide Feedback # active ## active **This is an abbreviation for active component.** ## active component A SNOMED CT component that is intended for use. #### Notes * Release files contain *active* and inactive components to provide a historical record of the terminology at different points in time. * A component is active when the most recent row with the relevant *component*.*id* in the full release file has the value *component*.*active* =1 (one). The most recent row for a component is determined based on the *component*.*effectiveTime* value. Provide Feedback # active component ## active component A SNOMED CT component that is intended for use. #### Notes * Release files contain *active* and inactive components to provide a historical record of the terminology at different points in time. * A component is active when the most recent row with the relevant *component*.*id* in the full release file has the value *component*.*active* =1 (one). The most recent row for a component is determined based on the *component*.*effectiveTime* value. Provide Feedback # active concept ## active concept A concept that is intended for use. #### Notes * Release files contain *active* and inactive concepts to provide a historical record of the terminology at different points in time. * A concept is active when the most recent row with the relevant *concept*.*id* in the full release file has the value *concept*.*active* =1 (one). The most recent row for a concept is determined based on the *concept*.*effectiveTime* value. Provide Feedback # active description ## active description A description that is intended for use. #### Notes * Release files contain *active* and inactive descriptions to provide a historical record of the terminology at different points in time. * A description is active when the most recent row with the relevant *description*.*id* in the full release file has the value *description*.*active* =1 (one). The most recent row for a description is determined based on the *description*.*effectiveTime* value. Provide Feedback # active reference set member ## active reference set member A reference set member that is intended for use. #### Notes * Release files contain *active* and inactive reference set members to provide a historical record of the terminology at different points in time. * A *reference set member* is active when the most recent row with the relevant *id* in the full release file has the value *active* =1 (one). The most recent row for a *reference set member* is determined based on the *effectiveTime* value. ## Provide Feedback # active relationship ## active relationship A relationship that is intended for use. #### Notes * Release files contain *active* and inactive relationships to provide a historical record of the terminology at different points in time. * A relationship is active when the most recent row with the relevant *relationship*.*id* in the full release file has the value *relationship*.*active* =1 (one). The most recent row for a relationship is determined based on the *relationship*.*effectiveTime* value. ## Provide Feedback # affiliate ## Affiliate **This is an abbreviation for Affiliate Licensee.** ## Affiliate Licensee An organization or individual that has been issued a license to use SNOMED CT by SNOMED International. #### Notes * Usage must be in accordance with the SNOMED CT Affiliate License Agreement. ## Alternatives * **Affiliate** * **IHTSDO Affiliate** * **SNOMED International Affiliate**\*\* ## Related Links * [SNOMED CT Affiliate Licence Agreement](http://snomed.org/license) Provide Feedback # affiliate edition ## Affiliate Edition **This is an abbreviation for SNOMED CT Affiliate Edition** ## SNOMED CT Affiliate Edition A set of SNOMED CT components and reference set members that either belong to a focus module identified by an Affiliate Licensee with an allocated extension namespace identifier, or belong to one of the modules on which that *module* depends. #### Notes * The *focus module* is part of the extension for which that Affiliate is responsible. * An *Affiliate Edition* may extend the SNOMED CT International Edition or a National Edition. Provide Feedback # affiliate license agreement ## Affiliate License Agreement The agreement between an Affiliate Licensee and SNOMED International. #### Notes * The agreement allows developers and implementers to use the SNOMED CT International Release and distribute the terminology to their sub-licensees as part of a software system. ## Alternatives * **Affiliate License** * **SNOMED CT Affiliate License Agreement** ## Related Links * [SNOMED International Affiliate Licence Agreement](https://www.snomed.org/get-snomed) Provide Feedback # affiliate license ## Affiliate License **This is an abbreviation for Affiliate License Agreement** ## Affiliate License Agreement The agreement between an Affiliate Licensee and SNOMED International. #### Notes * The agreement allows developers and implementers to use the SNOMED CT International Release and distribute the terminology to their sub-licensees as part of a software system. ## Alternatives * **Affiliate License** * **SNOMED CT Affiliate License Agreement** ## Related Links * [SNOMED International Affiliate Licence Agreement](https://www.snomed.org/get-snomed) Provide Feedback # affiliate licensee ## Affiliate Licensee An organization or individual that has been issued a license to use SNOMED CT by SNOMED International. #### Notes * Usage must be in accordance with the SNOMED CT Affiliate License Agreement. ## Alternatives * **Affiliate** * **IHTSDO Affiliate** * **SNOMED International Affiliate**\*\*\ \*\* ## Related Links * [SNOMED CT Affiliate Licence Agreement](http://snomed.org/license) Provide Feedback # alpha package ## alpha package **This is an abbreviation for alpha release package.** ## alpha release package A SNOMED CT release package made available only for initial review and testing by implementers and other stakeholders. #### Notes * An *alpha release package* must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * An *alpha release* is used to test the format and content of the SNOMED CT release. Feedback is elicited and changes are made prior to publication of the beta release. * *Alpha releases* were formerly known as a technology preview releases. ## Alternatives * **Alpha package** * **Alpha release** Provide Feedback # alpha release package ## alpha release package A SNOMED CT release package made available only for initial review and testing by implementers and other stakeholders. #### Notes * An *alpha release package* must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * An *alpha release* is used to test the format and content of the SNOMED CT release. Feedback is elicited and changes are made prior to publication of the beta release. * *Alpha releases* were formerly known as a technology preview releases. ## Alternatives * **Alpha package** * **Alpha release** Provide Feedback # alpha release ## alpha release **This is an abbreviation for alpha release package.** ## alpha release package A SNOMED CT release package made available only for initial review and testing by implementers and other stakeholders. #### Notes * An *alpha release package* must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * An *alpha release* is used to test the format and content of the SNOMED CT release. Feedback is elicited and changes are made prior to publication of the beta release. * *Alpha releases* were formerly known as a technology preview releases. ## Alternatives * **Alpha package** * **Alpha release** Provide Feedback # american national standards institute ## American National Standards Institute A private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. #### Notes * The organization also coordinates U.S. standards with international standards. ## Alternatives * **ANSI** ## Related Links * Provide Feedback # ancestor ## ancestor **This is an abbreviation for supertype ancestor.** ## supertype ancestor A concept that is a supertype of a specified concept. #### Notes * A *supertype ancestor* Includes the supertype parents and the supertype parents of each supertype parent, until the root concept is reached. * The term *supertype* is synonymous with supertype ancestor. However, it is sometime helpful to use the term *supertype ancestor* to emphasize inclusion of all *supertypes* not just supertype parents. #### Example * The figure below shows an example hierarchy in which concept *S* has seven *supertype ancestors* A, B, D, E, I, J and K.

Figure 1: Hierarchy Illustration - Subtype ancestors

## Alternatives * **Ancestor** Provide Feedback # annotation ## annotation Is additional information that can be associated to SNOMED CT components and reference set members. #### Notes * This extra information may be of value when evaluating a particular change to a SNOMED component or aid in implementation of SNOMED CT. * Annotations are non-defining, so they do not have any impact on the classification of SNOMED CT concepts. * Annotations are not mandatory for all components or reference set members; they can be used as needed for a particular use case. ## Alternatives * **SNOMED CT annotations** Provide Feedback # ansi ## ANSI **This is an abbreviation for American National Standards Institute.** ## American National Standards Institute A private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. #### Notes * The organization also coordinates U.S. standards with international standards. ## Alternatives * **ANSI** ## Related Links * Provide Feedback # api ## API **This is an abbreviation for Application Programming Interface.** ## Application Programming Interface A set of rules and specifications that enable communication between software programs. #### Notes * The way an *application programming interface* operates is similar to a user interface, which facilitates interaction between humans and computers. ## Alternatives * **API** ## Related Links * Wikipedia * [Application programming interface](https://en.wikipedia.org/wiki/Application_programming_interface) Provide Feedback # application programming interface ## application programming interface A set of rules and specifications that enable communication between software programs. #### Notes * The way an *application programming interface* operates is similar to a user interface, which facilitates interaction between humans and computers. ## Alternatives * **API** ## Related Links * Wikipedia * [Application programming interface](https://en.wikipedia.org/wiki/Application_programming_interface) Provide Feedback # attribute ## attribute **This is an abbreviation for concept model attribute.** ## concept model attribute A characteristic of the meaning of a concept or the nature of a refinement. #### Notes * An *attribute* is assigned a value (attribute value pair) when used in the definition of a concept or in a postcoordinated expression. * The *attributes* that can be used in *definitions* or *refinements* are represented by a concepts that are subtypes of the concept [410662002 | Concept model attribute (attribute)|](http://snomed.info/id/410662002) . * The SNOMED CT concept model specifies: * The concept model domains which each specific *attribute* can be applied; and * The concept model range of values that can be applied to each specific *attribute*. #### Example * The attribute [116676008 | Associated morphology|](http://snomed.info/id/116676008) * is one of the *attributes* that can be applied to concepts in the [404684003 | Clinical finding|](http://snomed.info/id/404684003) domain; and * its range includes [49755003 | Morphologically abnormal structure (morphologic abnormality)|](http://snomed.info/id/49755003) and its subtypes. ## Alternatives * **Attribute** * **Role** Provide Feedback # attribute cardinality constraint ## attribute cardinality constraint A constraint on the number of times that a specific attribute may be included in the same concept definition or expression. #### Notes * Constraints on *attribute cardinality* apply only to non-redundant attributes. A redundant attribute is an attribute with a value that is subsumed by another attribute in the same *concept* definition or *expression*. * Cardinality constraints are represented by square brackets containing a minimum value value represented as an integer, optionally followed by two dots and a maximum value represented as an integer or as an asterisk \*\*\*\*\*. * If the maximum is omitted then the maximum cardinality is the same as the minimum cardinality. * If the maximum is an asterisk \*\*\*\*\* the maximum cardinality is unlimited. #### Examples * The following expression constraint is satisfied by any clinical finding whose definition has two or more non-redundant finding sites, irrespective of the attribute group in which they are contained. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) : \[2..\*] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) Provide Feedback # attribute cardinality ## attribute cardinality **This is a synonym for attribute cardinality constraint.** ## attribute cardinality constraint A constraint on the number of times that a specific attribute may be included in the same concept definition or expression. #### Notes * Constraints on *attribute cardinality* apply only to non-redundant attributes. A redundant attribute is an attribute with a value that is subsumed by another attribute in the same *concept* definition or *expression*. * Cardinality constraints are represented by square brackets containing a minimum value value represented as an integer, optionally followed by two dots and a maximum value represented as an integer or as an asterisk \*\*\*\*\*. * If the maximum is omitted then the maximum cardinality is the same as the minimum cardinality. * If the maximum is an asterisk \*\*\*\*\* the maximum cardinality is unlimited. #### Examples * The following expression constraint is satisfied by any clinical finding whose definition has two or more non-redundant finding sites, irrespective of the attribute group in which they are contained. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) : \[2..\*] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) Provide Feedback # attribute group cardinality constraint ## attribute group cardinality constraint A constraint on the number of times that an attribute group may be included in the same concept definition or expression. #### Notes * Cardinality constraints are represented by square brackets containing a minimum value value represented as an integer, optionally followed by two dots and a maximum value represented as an integer or as an asterisk \*\*\*\*\*. * If the maximum is omitted then the maximum cardinality is the same as the minimum cardinality. * If the maximum is an asterisk \*\*\*\*\* the maximum cardinality is unlimited. * *Attribute group cardinality* is NOT the same as attribute in group cardinality. Attribute in group cardinality constraint is defined as: ``` * A constraint on the number of times that a specific attribute may be included in the same attribute group. ``` \_\_ #### Examples * The expression constraint below is satisfied only by products with one, two or three attribute groups, which each contain at least one active ingredient relationship. < [373873005 |Pharmaceutical / biologic product|](http://snomed.info/id/373873005) :\ \[1..3] { [127489000 |Has active ingredient|](http://snomed.info/id/127489000) = < [105590001 |Substance|](http://snomed.info/id/105590001) } Provide Feedback # attribute group ## attribute group An association between a set of attribute value pairs that causes them to be considered together within a concept definition or postcoordinated expression. #### Notes * When an *attribute group* is represented as a group of defining relationships it is usually referred to as a *relationship group.* #### Example * [| Cholecystectomy with exploration of common duct|](http://snomed.info/id/45993005) has two different attribute groups: * [| Method|](http://snomed.info/id/260686004) [| Exploration - action|](http://snomed.info/id/281615006) *is grouped with* [| Procedure site - Direct (attribute)|](http://snomed.org/fictid) [| Common bile duct structure|](http://snomed.info/id/79741001) * [| Method|](http://snomed.info/id/260686004) [| Excision - action|](http://snomed.info/id/129304002) *is grouped with* [| Procedure site - Direct (attribute)|](http://snomed.org/fictid) [| Gallbladder structure|](http://snomed.info/id/28231008) * If these attributes were not grouped, this procedure would incorrectly classified as a subtype of [| Excision of common bile duct|](http://snomed.info/id/6402000) . ## Alternatives * **Relationship group** * **Role group** Provide Feedback # attribute hierarchy ## attribute hierarchy A hierarchy in which a set of concept model attributes are linked to a more general *attribute.* #### Notes * Attribute hierarchies are represented in release files: * as subtype relationships in the relationship file. * as OWL SubObjectPropertyOf() axioms in the OWL Expression Reference Set file. #### Examples * * * **Attribute hierarchy represented by three OWL expressions**\ \[code] SubObjectPropertyOf(:733930001 :774081006)\ SubObjectPropertyOf(:733931002 :774081006)\ SubObjectPropertyOf(:733932009 :774081006)\ \[/code] Provide Feedback # attribute in group cardinality constraint ## attribute in group cardinality constraint A constraint on the number of times that a specific attribute may be included in the same attribute group. #### Notes * Constraints on *attribute in group cardinality* apply only to non-redundant attributes. A redundant attribute is an attribute with a value that is subsumed by another attribute in the same group. * Cardinality constraints are represented by square brackets containing a minimum value value represented as an integer, optionally followed by two dots and a maximum value represented as an integer or as an asterisk \*\*\*\*\*. * If the maximum is omitted then the maximum cardinality is the same as the minimum cardinality. * If the maximum is an asterisk \*\*\*\*\* the maximum cardinality is unlimited. * *Attribute in group cardinality* is NOT the same as attribute group cardinality constraint. Attribute group cardinality constraint is defined as: ``` * A constraint on the number of times that an attribute group may be included in the same concept definition or expression. ``` \_\_ #### Examples * The following expression constraint restricts *cardinality in-group* and would require a clinical finding whose definition has no more than one finding site in each group. However, it permits multiple groups to exist as there are cardinality constraints on the group. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) :\ {\[0..1] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) } * In contrast, the following expression constraint is satisfied by any clinical finding whose definition has two or more non-redundant finding sites, irrespective of the attribute group in which they are contained. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) : \[2..\*] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) * A clinical finding could satisfy both the above constraints by have two or more groups each of which contains one finding site. Provide Feedback # attribute in group cardinality ## attribute in group cardinality The number of times that a specific attribute is included in the same attribute group. #### Notes * This term may sometimes be used as an informal abbreviation for attribute in group cardinality constraint which is defined as follows: * A constraint on the number of times that a specific attribute may be included in the same attribute group. * *Attribute in group cardinality* is **not** the same as attribute cardinality or attribute group cardinality. ## Alternatives * **Cardinality in group** Provide Feedback # attribute name ## attribute name The concept that represents the attribute type in a defining relationship or postcoordinated expression. #### Notes * An *attribute name* with an attribute value is referred to as an attribute value pair. * An attribute value pair can represent a defining characteristic of a concept or an expression refinement. * In the *relationship file* , the *attribute name* is represented by the relationship.*typeId* and the attribute value by the relationship.*destinationId*.\_\ \_ * Theconcepts that can be used to name attributes are: 1. ``` * [ 116680003 | Is a (attribute)|](http://snomed.info/id/116680003 "116680003 | Is a \(attribute\) |") and ``` * subtypes of [410662002 | Concept model attribute|](http://snomed.info/id/410662002) ## Alternatives * **Relationship type** Provide Feedback # attribute relationship ## attribute relationship A relationship between two concepts in which one concept specifies the value of a defining characteristic of the other concept. #### Notes * In the relationships file an attribute relationship is represented by three concept identifiers: * **SourceId** represents the concept defined by the attribute relationship. * **TypeId** represents the attribute, which has a value that is a subtype of [410662002 | Concept model attribute|](http://snomed.info/id/410662002) . * **DestinationId** represents the value applied to that attribute. * Concepts are defined by a combination of *attribute relationships* and subtype relationships. #### Example * The table below shows an example of three *attribute* *relationships* as it appears in the three significant columns of the relationships file: | sourceId | typeId | destinationId | | ---------- | ------------------------- | ------------------------------------------- | | \[ 6025007 | Laparoscopic appendectomy | ]\( "6025007 | | \[ 6025007 | Laparoscopic appendectomy | ]\( "6025007 | | \[ 6025007 | Laparoscopic appendectomy | ]\( "6025007 | Provide Feedback # attribute value pair ## attribute value pair A combination of an attribute name and an attribute value used to specify a defining characteristic of a concept. #### Notes * The attribute name \_\_ identifies the type of information and the attribute value \_\_ provides a value \_.\ \_ * An attribute value pair can represent a defining characteristic of a concept or an expression refinement. * In the *relationship file* , the *attribute name* is represented by the relationship.*typeId* and the attribute value by the relationship.*destinationId*. Provide Feedback # attribute value A concept that represents the target of a relationship or the value of an expression refinement in a postcoordinated expression. ### Notes * An *attribute value* applied to an attribute name is referred to as an attribute value pair. * An attribute value pair can represent a defining characteristic of a concept or an expression refinement. * In the *Relationship file* , the attribute name is represented by the Relationship.*typeId* and the *attribute value* by the Relationship.*destinationId*. Provide Feedback # augmented backus naur form ## Augmented Backus-Naur Form A language used to define the formal syntax of another language in computer science. #### Notes * *Augmented Backus-Naur Form* is: ``` * used to define syntax for Internet specifications. ``` ``` * defined by Internet Standard 68, RFC 5234. ``` ## Alternatives * ABNF ## Related Links * Internet Engineering Task Force * [Augmented BNF for Syntax Specifications](https://tools.ietf.org/html/rfc5234) * Wikipedia * [Augmented Backus-Naur form](https://en.wikipedia.org/wiki/Augmented_Backus%E2%80%93Naur_form) Provide Feedback # author ## author **This is an abbreviation for SNOMED CT author.** ## SNOMED CT author A person responsible for creating or editing SNOMED CT concepts, concept definitions, and descriptions. ## Alternatives * **Author** * **Editor** * **Modeler** * **SNOMED CT editor** * **SNOMED CT modeler** Provide Feedback # authoring ## authoring **This is an abbreviation for SNOMED CT authoring.** ## SNOMED CT authoring The process of creating or editing SNOMED CT concepts, concept definitions and descriptions. ## Alternatives * **Authoring** * **Modeling** * **SNOMED CT modeling** Provide Feedback # authoritative concept A concept with a specific meaning defined by an authoritative source. ### Notes * National or international professional bodies or standards organizations are sources of authoritative concepts. ### Examples * Taxonomic groupings of organisms are only added to the *SNOMED CT* International Release where an appropriate authoritative source reference is provided (see Organism groupings) Provide Feedback # automatic classification ## automatic classification **This is a synonym for description logic classification.** ## description logic classification A process that generates a set of logically consistent inferences by applying description logic rules to the stated view of concept definitions. ## Alternatives * **Automatic classification** Provide Feedback # axiom ## axiom A true statement that serves as a premise or starting point for further reasoning. #### Notes * The *axioms* that specify SNOMED CT concept definition release files as SNOMED CT relationships or as OWL axioms that conform to the OWL Functional Syntax. #### Change Notices * Since July 2019 all axioms in the stated view of concept definitions have been represented as OWL axioms.\ Before July 2018, the stated view was represented using relationships and during a transitional period ending in July 2019 some *axioms* in stated view were represented using the OWL functional syntax. * The inferred view \_\_ of concept definitions continues to be represented using relationships. ## Alternatives * **OWL axiom** Provide Feedback # B Provide Feedback # baseline ## baseline **Superseded by - Production release package.** ## Production release package A final, formally endorsed SNOMED CT release package intended for live use in appropriately licensed operational systems. #### Notes * A *production release package* represents the authoritative release of the product. Implementers can use it in operational clinical systems. * The *production release* status indicates that the releasing party (SNOMED International or the owner of the extension) commits to maintain the release history. Thus the historical audit trail is maintained through the product's lifetime. ## Alternatives * **Production package** * **Production release** Provide Feedback # beta package ## beta package **This is a synonym for beta release package.** ## beta release package A SNOMED CT release package made available for review and testing only. #### Notes * Implementers and other stakeholders review and test the *beta release*. * The *beta release package* is made available prior to the production release. It must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * The *beta release* status indicates it is expected to subsequently be confirmed as a production release. If there is significant issue in format or content, it may be withdrawn, or replaced with an updated *beta release package*. Whether or not it becomes a production release is decided shortly before the due date for the next release. If a *beta release* is subsequently confirmed as a production release, all updates are fully version-tracked from the date of the *beta release*. * Beta releases were formerly known as candidate baseline releases. ## Alternatives * **Beta package** * **Beta release** Provide Feedback # beta release package ## beta release package A SNOMED CT release package made available for review and testing only. #### Notes * Implementers and other stakeholders review and test the *beta release*. * The *beta release package* is made available prior to the production release. It must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * The *beta release* status indicates it is expected to subsequently be confirmed as a production release. If there is significant issue in format or content, it may be withdrawn, or replaced with an updated *beta release package*. Whether or not it becomes a production release is decided shortly before the due date for the next release. If a *beta release* is subsequently confirmed as a production release, all updates are fully version-tracked from the date of the *beta release*. * Beta releases were formerly known as candidate baseline releases. ## Alternatives * **Beta package** * **Beta release** Provide Feedback # beta release ## beta release **This is an abbreviation for beta release package.** ## beta release package A SNOMED CT release package made available for review and testing only. #### Notes * Implementers and other stakeholders review and test the *beta release*. * The *beta release package* is made available prior to the production release. It must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * The *beta release* status indicates it is expected to subsequently be confirmed as a production release. If there is significant issue in format or content, it may be withdrawn, or replaced with an updated *beta release package*. Whether or not it becomes a production release is decided shortly before the due date for the next release. If a *beta release* is subsequently confirmed as a production release, all updates are fully version-tracked from the date of the *beta release*. * Beta releases were formerly known as candidate baseline releases. ## Alternatives * **Beta package** * **Beta release** Provide Feedback # binomial format ## binomial format **This is a synonym for binomial nomenclature.** ## binomial nomenclature The formal system for the two-part names of species. #### Notes * The *binomial nomenclature* is standardized and internationally accepted. * The two parts of the \_binomial *nomenclature* \_ are the genus and species. * SNOMED CT includes the *binomial nomenclature* name for organism species and follows the convention of using uppercase for the initial letter of the genus name and lowercase for the initial letter of the species name. Example * The concept [24224000 | Brucella abortus (organism)|](http://snomed.info/id/24224000) has the following associated terms: Fully specified name\ [|Brucella abortus (organism)|](http://snomed.info/id/24224000)\ Preferred term\ [|Brucella abortus|](http://snomed.info/id/24224000)\ Other synonyms\ [|Brucella melitensis biovar abortus|](http://snomed.info/id/24224000)\ [|Bacillus abortus|](http://snomed.info/id/24224000) Note that both the fully specified name and the preferred term use the binomial nomenclature . ## Alternatives * **Binomial format** ## Links * [International Code of Nomenclature for algae, fungi, and plants](https://www.iapt-taxon.org/nomen/main.php?page=title) * [International Code of Zoological Nomenclature](http://www.nhm.ac.uk/hosted-sites/iczn/code/) * Wikipedia * [Binomial nomenclature](https://en.wikipedia.org/wiki/Binomial_nomenclature) Provide Feedback # binomial nomenclature ## binomial nomenclature The formal system for the two-part names of species. #### Notes * The *binomial nomenclature* is standardized and internationally accepted. * The two parts of the \_binomial *nomenclature* \_ are the genus and species. * SNOMED CT includes the *binomial nomenclature* name for organism species and follows the convention of using uppercase for the initial letter of the genus name and lowercase for the initial letter of the species name. Example * The concept [24224000 | Brucella abortus (organism)|](http://snomed.info/id/24224000) has the following associated terms: Fully specified name\ [|Brucella abortus (organism)|](http://snomed.info/id/24224000)\ Preferred term\ [|Brucella abortus|](http://snomed.info/id/24224000)\ Other synonyms\ [|Brucella melitensis biovar abortus|](http://snomed.info/id/24224000)\ [|Bacillus abortus|](http://snomed.info/id/24224000) Note that both the fully specified name and the preferred term use the binomial nomenclature . ## Alternatives * **Binomial format** ## Links * [International Code of Nomenclature for algae, fungi, and plants](https://www.iapt-taxon.org/nomen/main.php?page=title) * [International Code of Zoological Nomenclature](http://www.nhm.ac.uk/hosted-sites/iczn/code/) * Wikipedia * [Binomial nomenclature](https://en.wikipedia.org/wiki/Binomial_nomenclature) Provide Feedback # browser ## browser **This is an abbreviation for SNOMED CT browser.** ## SNOMED CT browser A software application that provides a user interface through which to explore SNOMED CT content. #### Note * A typical *SNOMED CT browser* can locate concepts and descriptions by identifiers and by searching the text of description *terms*. * Various views of located concepts may be displayed including the set of related descriptions, the hierarchical relationships and other defining relationships. ## Alternatives * **Browser** * **Terminology browser** ## Related Links * [SNOMED CT Browser](https://browser.ihtsdotools.org) * [Other SNOMED CT browsers](https://www.implementation.snomed.org/browsers) Provide Feedback # C Provide Feedback # c-npu ## C-NPU A coded terminology used in clinical laboratory sciences. #### Notes * *C-NPU* is maintained by the International Federation of Clinical Chemists (IFCC) in collaboration with the International Union of Pure and Applied Chemistry (IUPAC). ## Alternatives * **IFCC-IUPAC** * **Nomenclature, Properties and Units** * **NPU** ## Related Links * [Nomenclature, Properties and Units (C-NPU) in collaboration with International Union of Pure and Applied Chemistry (IUPAC)](http://www.ifcc.org/ifcc-scientific-division/sd-committees/c-npu/) Provide Feedback # candidate baseline ## candidate baseline **Superseded by - Beta release package.** ## Beta release package A SNOMED CT release package made available for review and testing only. #### Notes * Implementers and other stakeholders review and test the *beta release*. * The *beta release package* is made available prior to the production release. It must not be used in production clinical systems or in clinical settings. This includes Affiliate Licensees or any third parties, except those who have formally committed to test it. * The *beta release* status indicates it is expected to subsequently be confirmed as a production release. If there is significant issue in format or content, it may be withdrawn, or replaced with an updated *beta release package*. Whether or not it becomes a production release is decided shortly before the due date for the next release. If a *beta release* is subsequently confirmed as a production release, all updates are fully version-tracked from the date of the *beta release*. * Beta releases were formerly known as candidate baseline releases. ## Alternatives * **Beta package** * **Beta release** Provide Feedback # canonical form ## canonical form A serialized representation of a SNOMED CT expression produced by applying a set of rules that ensure a single unique representation for any expression. #### Notes * Expressions that contain exactly the same concept identifiers and refinements, may differ from one another in the following ways: * Inclusion of whitespace between elements * Inclusion of specific terms associated with identified concepts. * The order in which focus concepts, refinements, attributes, and attribute groups appear. * The *canonical form* is generated by removing whitespace and terms from an expression and arranging the focus concepts, refinements, attributes, and attribute groups in a standard order. * If *canonical form* rules are applied to a normal form expression, the result is a single unique rendering of the meaning represented by that expression. ## Alternatives * **Canonical representation** ## Related Links * Wikipedia * [Canonical form](https://en.wikipedia.org/wiki/Canonical_form) Provide Feedback # cardinality ## cardinality The actual or permitted number of elements in a set or other grouping. #### Notes * Modeling rules include constraints on the minimum and maximum *cardinality* of particular attributes or associations between classes. #### Example * A cardinality of *\[1..5]* means that all clinical meanings that satisfy the given expression constraint must have at least one and at most five attributes, that match the given attribute criteria. Provide Feedback # cardinality in group constraint ## cardinality in group constraint **This is a synonym for attribute in group cardinality constraint.** ## attribute in group cardinality constraint A constraint on the number of times that a specific attribute may be included in the same attribute group. #### Notes * Constraints on *attribute in group cardinality* apply only to non-redundant attributes. A redundant attribute is an attribute with a value that is subsumed by another attribute in the same group. * Cardinality constraints are represented by square brackets containing a minimum value value represented as an integer, optionally followed by two dots and a maximum value represented as an integer or as an asterisk \*\*\*\*\*. * If the maximum is omitted then the maximum cardinality is the same as the minimum cardinality. * If the maximum is an asterisk \*\*\*\*\* the maximum cardinality is unlimited. * *Attribute in group cardinality* is NOT the same as attribute group cardinality constraint. Attribute group cardinality constraint is defined as: ``` * A constraint on the number of times that an attribute group may be included in the same concept definition or expression. ``` \_\_ #### Examples * The following expression constraint restricts *cardinality in-group* and would require a clinical finding whose definition has no more than one finding site in each group. However, it permits multiple groups to exist as there are cardinality constraints on the group. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) :\ {\[0..1] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) } * In contrast, the following expression constraint is satisfied by any clinical finding whose definition has two or more non-redundant finding sites, irrespective of the attribute group in which they are contained. < [404684003 |Clinical finding|](http://snomed.info/id/404684003) : \[2..\*] [363698007 |Finding site|](http://snomed.info/id/363698007) = < [91723000 |Anatomical structure|](http://snomed.info/id/91723000) * A clinical finding could satisfy both the above constraints by have two or more groups each of which contains one finding site. Provide Feedback # cardinality in group ## cardinality in group **This is a synonym for attribute in group cardinality.** ## attribute in group cardinality The number of times that a specific attribute is included in the same attribute group. #### Notes * This term may sometimes be used as an informal abbreviation for attribute in group cardinality constraint which is defined as follows: * A constraint on the number of times that a specific attribute may be included in the same attribute group. * *Attribute in group cardinality* is **not** the same as attribute cardinality or attribute group cardinality. ## Alternatives * **Cardinality in group** Provide Feedback # cds ## CDS **This is an abbreviation for clinical decision support.** ## clinical decision support A service that assists clinicians, caregivers, or patients in healthcare and/or treatment decisions. Notes * A clinical decision support system is a computer system or software application designed to assist clinicians, caregivers, or patients in healthcare and/or treatment decisions. ## Alternatives * **CDS** Provide Feedback # cdss ## CDSS **This is an abbreviation for clinical decision support system.** ## clinical decision support system A computer system or software application designed to assist clinicians, caregivers, or patients in healthcare and/or treatment decisions. Notes * Typically a clinical decision support system responds to triggers, such as specific signs or symptoms, diagnoses, laboratory test results, medication selections, or complex combinations of such triggers. The system then provides information or recommendations relevant to the specific patient. ## Alternatives * **CDSS** Provide Feedback # cen tc251 ## CEN TC251 A technical committee of the European Committee for Standardization (CEN) with a focus on Health Information and Communications Technology (ICT). #### Notes * The full name of this committee is CEN/Technical Committee 251 - Health informatics. * The goal of CEN TC251 is to achieve compatibility and interoperability between independent systems and to enable modularity in Electronic Health Record systems. ## Related Links * [CEN/TC 251 - Health informatics](https://standards.cen.eu/dyn/www/f?p=204:7:0::::FSP_ORG_ID:6232\&cs=18CA078392807EDD402B798AAEF1644E1) * [CEN, Information and Communication Technology](https://www.cencenelec.eu/standards/Sectors/ICT/Pages/default.aspx) Provide Feedback # cen ## CEN **This is an abbreviation for European Committee for Standardization.** ## European Committee for Standardization A standards organization whose mission is to foster the economy of the European Union in global trading, the welfare of European citizens, and the environment. #### Notes * The European Committee for Standardization is a major provider of European standards and technical specifications. ## Alternatives * **CEN** * **Comité Européen de Normalisation** * **Europäiches Komitee für Normung** ## Related Links * [European Committee for Standardization](http://www.cen.eu) * CEN TC251 - Health informatics Provide Feedback # cf expression ## CF expression **This is a synonym for classifiable form expression.** ## classifiable form expression A syntactically valid and concept model compliant representation of the close-to-user form expression. #### Notes * The *classifiable form expression* serves as the input to the classifier, enabling compositional expressions to be classified with SNOMED CT content * In the *classifiable form expression* , ungrouped attributes and role groups have been validated and appropriately applied to the definition of the focus concept ## Alternatives * CF expression Provide Feedback # check digit ## check-digit The last digit of a SNOMED CT Identifier, which is used to validate the identifier. #### Notes * Applications can use the *check-digit* to identify SNOMED CT codes that have been entered or communicated incorrectly. * The *check-digit* is calculated using the *Verhoeff algorithm*. Provide Feedback # child ## child **This is an abbreviation for subtype child.** ## subtype child A concept that has a direct [| is a|](http://snomed.info/id/116680003) subtyperelationship to a specified concept. #### Notes * See also subtype and subtype descendant. #### Example * The figure below shows an example hierarchy in which concept *C* has two *subtype children* ,*F and G*.

Figure 1: Hierarchy Illustration - Subtype children

## Alternatives * **Child** * **Children** * **Subtype children** Provide Feedback # children ## children **This is an abbreviated plural for subtype child.** ## subtype child A concept that has a direct [| is a|](http://snomed.info/id/116680003) subtyperelationship to a specified concept. #### Notes * See also subtype and subtype descendant. #### Example * The figure below shows an example hierarchy in which concept *C* has two *subtype children* ,*F and G*.

Figure 1: Hierarchy Illustration - Subtype children

## Alternatives * **Child** * **Children** * **Subtype children** Provide Feedback # cis ## CIS **This is an abbreviation for clinical information system.** ## clinical information system A computer-based system that collects, stores, manipulates, and supplies clinical information to support the delivery of healthcare services to individual people and populations. ## Alternatives * **CIS** Provide Feedback # classifiable form expression ## classifiable form expression A syntactically valid and concept model compliant representation of the close-to-user form expression. #### Notes * The *classifiable form expression* serves as the input to the classifier, enabling compositional expressions to be classified with SNOMED CT content * In the *classifiable form expression* , ungrouped attributes and role groups have been validated and appropriately applied to the definition of the focus concept ## Alternatives * CF expression Provide Feedback # classifier ## classifier **This is an abbreviation for description logic classifier.** ## description logic classifier A software tool that applies the rules of description logic to a set of axioms to infer additional relationships between concepts. #### Notes * SNOMED CT concept definitions are processed by a *description logic classifier* to generate inferred subtype hierarchies. * SNOMED CT expressions can also be processed by a *description logic classifier* to make inferences that enable more complete and precise selective retrieval to support analytics. ## Alternatives * **Classifier** Provide Feedback # clinical decision support system ## clinical decision support system A computer system or software application designed to assist clinicians, caregivers, or patients in healthcare and/or treatment decisions. Notes * Typically a clinical decision support system responds to triggers, such as specific signs or symptoms, diagnoses, laboratory test results, medication selections, or complex combinations of such triggers. The system then provides information or recommendations relevant to the specific patient. ## Alternatives * **CDSS** ## Provide Feedback # clinical decision support ## clinical decision support A service that assists clinicians, caregivers, or patients in healthcare and/or treatment decisions. Notes * A clinical decision support system is a computer system or software application designed to assist clinicians, caregivers, or patients in healthcare and/or treatment decisions. ## Alternatives * **CDS** Provide Feedback # clinical information system ## clinical information system A computer-based system that collects, stores, manipulates, and supplies clinical information to support the delivery of healthcare services to individual people and populations. ## Alternatives * **CIS** Provide Feedback # clinical situation ## clinical situation **This is a synonym for situation with explicit context.** ## situation with explicit context A concept that specifically defines the context of a clinical finding or procedure. #### Notes * A *situation with explicit context* is defined as a subtype of the situation to which it applies with an attribute associating it with the relevant clinical finding or procedure. #### Example * *Family history of diabetes mellitus* is a *situation with explicit context* concept. It defines the context as *family history* by indicating that the [408732007 | Subject relationship context|](http://snomed.info/id/408732007) is a [303071001 | Family member|](http://snomed.info/id/303071001) . * In contrast, *diabetes mellitus* itself is not a *situation with explicit context*. It can be used in many different situations including *family history* , *past medical history* or *current diagnosis*. ## Alternatives * **Clinical situation** * **Context** * **Explicit context** Provide Feedback # clinical terms version 3 ## Clinical Terms Version 3 **This is an abbreviation for NHS Clinical Terms Version 3.** ## NHS Clinical Terms Version 3 A source terminology used to develop SNOMED CT. #### Notes * SNOMED RT was also used with *NHS Clinical Terms Version 3* to develop SNOMED CT *.* * *NHS Clinical Terms Version 3* is UK Crown Copyright, distributed by the United Kingdom National Health Service (NHS), and is integrated into SNOMED CT. ## Alternatives * **CTV3** * **Read Codes Version 3** Provide Feedback # close to user form expression ## close to user form expression The faithful representation of the information as it was entered, and the primary stored and communicated view of clinical information encoded using SNOMED CT. #### Notes * The *close to user form expressio* n includes refinements applied by an application based on selections made in an entry form as well as those made explicitly * The *close to user form expression* does not include any additional relationships that are added based on classifier rules to make the expression complete or to normalize it ## Alternatives * CTUF expression Provide Feedback # code ## code ## Disambiguation * Meanings of the word *code* commonly used in connection with SNOMED CT and the services, applications and organizations that use SNOMED CT include: 1. SNOMED CT concept identifiers and expressions used to represent clinical meanings may sometimes be informally referred to as "SNOMED codes". 2. Codes in code systems or classifications that are used with or mapped to/from SNOMED CT. 3. Software code written in a computer programming language (or compiled as machine executable code) that determines the operation of an application or device. 4. Codes used to represent characters and symbols in computer storage and communication (e.g. UTF-8). 5. Cryptographic codes used to support secure access to and/or communication of data. Provide Feedback # collaborative space A web resource that assists organizations with communication and collaboration. ### Notes * SNOMED International collaborative spaces powered by Confluence: * Support communication within the organization and with its Members, Affiliates, and Advisory Groups. * Enable maintenance and publication of the SNOMED CT Document Library containing specifications, guides and other documents related to SNOMED CT. Provide Feedback # common terminology services 2 ## Common Terminology Services 2 An application programming interface (API) specification of the basic functional requirements used to query and access terminological content. #### Notes * *CTS2*\ \* Is an abbreviation for *Common Terminology Services 2.*\ \* Is used by healthcare software implementers.\ \* Defines the functional requirements of a set of service interfaces to allow the representation, access, and maintenance of terminology content either locally, or across a federation of terminology services nodes.\_\ \_\ \* Is specified as an API, rather than a set of data structures. This enables a wide range of terminological content to be integrated within a common framework, without the need for significant migration or revision.\ \* Was developed from the original [HL7 CTS specification](http://snomed.org/cts2) and is now a joint initiative between HL7 and the [Object Management Group (OMG)](http://www.omg.org/). ## Alternatives * **CTS2** * **HL7 CTS2** Provide Feedback # complement The set of elements that are **not** in a specified set. ### Notes * In set theory, the *complement* of set \*\* *A*\*\* refers to all elements not in set \*\* *A*\*\*. * In SNOMED CT, the *complement* of a \_subset \_of concepts consists of all concepts that are not in that subset. ### Example * The following expression constraint language defines the set of concepts that are subtypes of [442083009 | Anatomical or acquired body structure|](http://snomed.info/id/442083009) that are also part of the *complement* of the [723264001 | Lateralizable body structure reference set|](http://snomed.info/id/723264001) . The "MINUS" instruction excludes members of the reference set, so only concepts that are part of the *complement* of that set are included. < [442083009 |Anatomical or acquired body structure|](http://snomed.info/id/442083009)\ MINUS ^ [723264001 |Lateralizable body structure reference set|](http://snomed.info/id/723264001) Related Links * Wikipedia * [Complement (set theory)](https://en.wikipedia.org/wiki/Complement_\(set_theory\)) Provide Feedback # component history ## component history A record of creation or modification of a component between SNOMED CT versions. Provide Feedback # component version A representation of a SNOMED CT component at a particular point in time. ### Notes * In SNOMED CT release files each *component version* is represented as a single row with a unique combination of *component.id* and *component.effectivetime.* * The *component.id* uniquely identifies the component and is shared by other versions of that component. * The *component.effectiveTime* distinguishes different versions of the same component. It indicates the point in time at which that version became the authoritative version of that component. The *effectiveTime* of the first version of a component represents the time when it first became available for use. The *effectiveTime* of each subsequent version of a component represents the time when that version superseded the previous version. Provide Feedback # component ## component **This is an abbreviation for SNOMED CT component.** ## SNOMED CT component A concept, description, or relationship that conforms with the SNOMED CT logical model. #### Notes * *Components* are released and distributed in file formats that conform to the Release File Specification. * *Components* may be part of the SNOMED CT International Edition or in an authorized extension. ## Alternatives * **Component** Provide Feedback # compositional grammar ## compositional grammar **This is an abbreviation for SNOMED CT compositional grammar.** ## SNOMED CT compositional grammar The set of rules that govern the way in which SNOMED CT expressions are represented as a plain text string. ## Alternatives * **Compositional grammar** * **SCG** ## Related Links * **Specification** * Compositional Grammar Specification and Guide Provide Feedback # concept ## concept **This is an abbreviation for SNOMED CT concept.** ## SNOMED CT concept A clinical idea to which a unique concept identifier has been assigned. #### Notes * *SNOMED CT concepts* are distributed in the concept file. * *Concepts* are associated with descriptions that contain human-readable terms describing the concept. * *Concepts* are related to one another by relationships and OWL axioms that provide a formal logical definition of the *concept*. ## Alternatives * **Concept** ## Disambiguation Not to be confused with: * **Concept** , in its more general dictionary usages, referring to an idea or to a class of real-world entities. When working with SNOMED CT, the words "idea" or "meaning" are suggested instead of this more general use of concept. * **Concept identifier.** For clarity when referring to the identifier of a SNOMED CT concept, specifically refer to the "concept identifier", "concept id" or "code" rather than using the word concept. Provide Feedback # concept definition ## concept definition **This is an abbreviation for SNOMED CT concept definition.** ## SNOMED CT concept definition A set of one or more axioms that partially or sufficiently specify the meaning of a SNOMED CT concept. #### Notes * *Concept definitions* are represented in two ways in SNOMED CT release files:\ \* As a stated view represented by axioms that conform to the OWL Functional Syntax distributed in the OWL Expression Reference Set file.\ \* As an inferred view represented by defining relationships that are distributed in the relationship file. The *inferred view* is generated by applying description logic classification to the *stated view*. * *Concept definitions* include two distinct elements * Axioms that assert that a concept is a subtype of one or more other concepts. In the inferred view these are represented as subtype relationships. * Axioms that assert characteristics of a concept that distinguish it from its supertypes. In the inferred view these are represented as attribute relationships. #### Change Notice * Prior to July 2018 the stated view of concept definitions were represented by relationships in the Stated Relationships file. During a transitional period between July 2018 and July 2019 the OWL reference sets were introduced. Since the end of that transitional period in July 2019, the stated relationship file is no longer maintained or distributed. More information on the earlier representation of the stated view is provided in a historical note on Representation of the Logical Model - Before July 2018. ## Alternatives * **Concept definition** Provide Feedback # concept enumeration A set of SNOMED CT concept identifiers used to represent values for a property of a SNOMED CT component or reference set member. ### Notes * *Concept enumeration* serves the same purpose as more general approaches to providing enumerated lists of values (i.e. assigning a number to a value). However, the use of SNOMED CT concept identifier allows access to the human readable meaning of each enumeration using descriptions in the same way for other concepts. * The SNOMED CT concepts used to represent *concept enumerations* are usually subtype children (or descendants) of concepts in the SNOMED CT metadata hierarchy. Each possible value is represented by a single child concept. This allows updates to the permitted values to be tracked using the component history mechanism. ### Example * Concept enumerations for description.typeId: [900000000000446008 |Description type (core metadata concept)|](http://snomed.info/id/900000000000446008)\ [900000000000003001 |Fully specified name (core metadata concept)|](http://snomed.info/id/900000000000003001)\ [900000000000013009 |Synonym (core metadata concept)|](http://snomed.info/id/900000000000013009)\ [900000000000550004 |Definition (core metadata concept)|](http://snomed.info/id/900000000000550004) Provide Feedback # concept equivalence ## concept equivalence **This is a synonym for semantic equivalence.** ## semantic equivalence The relationship between two classes that have the same logical meaning. #### Notes * The equivalent classes may be represented in different ways for example as SNOMED CT concept definitions, SNOMED CT expressions, or axioms expressed using a syntax such as OWL Functional Syntax. * Semantic equivalence is represented by the Ξ symbol or by a sequence of three equals signs === . #### Example * The expression below asserts that the concept [80146002 | Appendectomy|](http://snomed.info/id/80146002) has *semantic equivalence* with [71388002 | Procedure|](http://snomed.info/id/71388002) with method [129304002 | Excision - action|](http://snomed.info/id/129304002) applied to the direct site [66754008 | Appendix structure|](http://snomed.info/id/66754008) . [80146002 |Appendectomy|](http://snomed.info/id/80146002)\ \=== [71388002 |Procedure|](http://snomed.info/id/71388002) :\ { [405813007 |Procedure site - Direct|](http://snomed.info/id/405813007) = [66754008 |Appendix structure|](http://snomed.info/id/66754008) ,\ [260686004 |Method|](http://snomed.info/id/260686004) = [129304002 |Excision - action|](http://snomed.info/id/129304002) } ## Alternatives * **Concept equivalence** * **Equivalence** Provide Feedback # concept identifier ## concept identifier A SNOMED CT identifier that uniquely identifies a concept. #### Notes * The *concept identifier* uniquely identifies the clinical idea represented by the concept. * The *concept identifier* is used in expressions and other information artefacts to represent the identified concept. Provide Feedback # concept model attribute ## concept model attribute A characteristic of the meaning of a concept or the nature of a refinement. #### Notes * An *attribute* is assigned a value (attribute value pair) when used in the definition of a concept or in a postcoordinated expression. * The *attributes* that can be used in *definitions* or *refinements* are represented by a concepts that are subtypes of the concept [410662002 | Concept model attribute (attribute)|](http://snomed.info/id/410662002) . * The SNOMED CT concept model specifies: * The concept model domains which each specific *attribute* can be applied; and * The concept model range of values that can be applied to each specific *attribute*. #### Example * The attribute [116676008 | Associated morphology|](http://snomed.info/id/116676008) * is one of the *attributes* that can be applied to concepts in the [404684003 | Clinical finding|](http://snomed.info/id/404684003) domain; and * its range includes [49755003 | Morphologically abnormal structure (morphologic abnormality)|](http://snomed.info/id/49755003) and its subtypes. ## Alternatives * **Attribute** * **Role** Provide Feedback # concept model domain ## concept model domain A set of concepts which the concept model permits to be defined or refined, using a particular set of attributes and ranges. #### Notes * A domain to which an attribute can be applied typically includes concepts in one or more branches of the subtype hierarchy. #### Examples * Section Procedure Attributes Summary of the SNOMED CT Editorial Guide defines the *domain* , attributes and ranges for | Procedure| . * The [| Procedure|](http://snomed.info/id/71388002) *domain* is defined as follows: << [71388002 |Procedure|](http://snomed.info/id/71388002) /\* the concept "Procedure" or any of its subtypes \*/ * The table row below shows how [| Procedure site|](http://snomed.info/id/363704007) , one of the many attributes applicable to the [| Procedure|](http://snomed.info/id/71388002) domain, is specified together with its range of permitted values. | **Attribute** | **Grouped** | **Cardinality** | **In Group Cardinality** | **Range Constraint** | | ------------------------------------------- | -------------- | ----------------------------------------------- | ------------------------ | ------------------------------------- | | \[ 363704007 | Procedure site | ]\( "363704007 | Procedure site | ") | | 1 | 0..\* | 0..\* | << \[ 442083009 | Anatomical or acquired body structure | | /\* "Anatomical or acquired body structure" | | | | | | or any of its subtypes. \*/ | | | | | ## Alternatives * **Domain** Provide Feedback # concept model range ## concept model range A set of values that the concept model permits to be applied to a specific attribute. #### Notes * The *range* of permitted values that can be applied to an attribute is formally specified using the expression constraint language. * The *range* is typically limited to concepts that are subtypes of one concept. However, in some cases a *range* may be specified to include subtypes of several concepts or members of a specified reference set. #### Example * The *concept model range* for the attribute [116676008 | Associated morphology|](http://snomed.info/id/116676008) is limited the concept [49755003 | Morphologically abnormal structure|](http://snomed.info/id/49755003) and its subtypes. This is specified by the following constraint: << [49755003 |Morphologically abnormal structure|](http://snomed.info/id/49755003) ## Alternatives * **Range** Provide Feedback # concept model ## concept model **This is an abbreviation for SNOMED CT concept model.** ## SNOMED CT concept model The set of rules that determines the permitted sets of relationships between particular types of concepts. #### Notes * The c *oncept model* specifies the attributes that can be applied to concepts in particular domains and the ranges of permitted values for each attribute. There are additional rules on the cardinality and grouping of particular types of relationships. ## Alternatives * **Concept model** Provide Feedback # confluence ## Confluence **This is the system that currently provides the SNOMED International collaborative space.** ## collaborative space A web resource that assists organizations with communication and collaboration. #### Notes * SNOMED International collaborative spaces powered by Confluence: * Support communication within the organization and with its Members, Affiliates, and Advisory Groups. * Enable maintenance and publication of the SNOMED CT Document Library containing specifications, guides and other documents related to SNOMED CT. Provide Feedback # conjunction ## conjunction An operator used to assert that two (or more) parts of a concept definition or expression constraint must both be true. #### Notes * *Conjunction* can be represented by the**AND** operator. A conjunction of *A* with *B* , means that both *A* **AND** *B* must be true. * *Conjunction* gives the same result as an *intersection*\*\*\*\* between the set of *concepts* or *expressions* for which *A* is true and the set of *concepts* or *expressions* for which *B* is true. #### Example * The following *expression constraint* is satisfied by clinical findings which are subtypes of both [19829001 | Disorder of lung (disorder)|](http://snomed.info/id/19829001) **AND** [301867009 | Edema of trunk (disorder)|](http://snomed.info/id/301867009) . < [19829001 |Disorder of lung|](http://snomed.info/id/19829001) AND < [301867009 |Edema of trunk|](http://snomed.info/id/301867009) Provide Feedback # constraint A rule that limits the attributes, values, and associations that may be applied to a particular component. ### Examples * A modeling *constraint* may limit the permissible defining relationships applied to a particular type of concept. * An instance data *constraint* may limit the permissible refinements that may be applied to a particular concept. Provide Feedback # context wrapper ## context wrapper The part of the SNOMED CT expression specifying the context of the focus concept. #### Examples * *Family history of asthma* can be represented by an expression in which the [195967001 | Asthma|](http://snomed.info/id/195967001) is nested within a *context wrapper* indicating family history. [281666001 |Family history of disorder (situation)|](http://snomed.info/id/281666001) : ⬅︎ Context wrapper\ { [246090004 |Associated finding|](http://snomed.info/id/246090004) = [195967001 |asthma|](http://snomed.info/id/195967001) ⬅︎ Focus concept\ } * Addition information can be added in the *context wrapper* to specify the family member affected by asthma. [281666001 |Family history of disorder (situation)|](http://snomed.info/id/281666001) : ⬅︎ Context wrapper\ { [408732007 |Subject relationship context|](http://snomed.info/id/408732007) = [72705000 |Mother|](http://snomed.info/id/72705000) , ⬅︎ ...\ [246090004 |Associated finding|](http://snomed.info/id/246090004) = [195967001 |asthma|](http://snomed.info/id/195967001) ⬅︎ Focus concept\ } Provide Feedback # context ## context The circumstances that form the setting in which a concept can be appropriately interpreted. #### Notes * Clear recording and appropriate interpretation of *context* is essential for safe use and accurate analysis of electronic health records. * The *context* in which a concept is used can be represented in various ways. Some of the possible representation are shown in the examples section below. * Appropriate interpretation of different representations of *context* can be facilitated by terminology binding techniques that resolve multiple models of use into a common model of meaning. #### Examples * A disease such as "asthma" might be referred to in various *contexts*. * A current presenting problem needing treatment * A past history recorded during assessment for treatment of another condition * A family history recorded routinely during a consultation * Family history of asthma can be recorded using SNOMED CT in several ways three of which are illustrated here. * Use of a single *concept* from the situation with explicit context domain: [160377001 |Family history: Asthma (situation)|](http://snomed.info/id/160377001) ``` * Application of a context wrapper to the _concept_ [ 195967001 | Asthma (disorder)|](http://snomed.info/id/195967001 "195967001 | Asthma \(disorder\) |") : ``` [57177007 |Family history with explicit context (situation)|](http://snomed.info/id/57177007) :\ { [246090004 |Associated finding (attribute)|](http://snomed.info/id/246090004) = [195967001 |Asthma (disorder)|](http://snomed.info/id/195967001) } ``` * Use of features of an electronic health record model, such as separate record sections for information with different _contexts_. ``` Family History Record Section\ [195967001 |Asthma (disorder|](http://snomed.info/id/195967001) ) ``` * Based on the definitions of these concepts, a description logic classifier will infer that first two representations above have precisely the same meaning. The third representation can be similarly resolved if the "Family History Record Section" has a _model or meaning binding_ to the [ 57177007 | Family history with explicit context (situation)|](http://snomed.info/id/57177007 "57177007 | Family history with explicit context \(situation\) |") wrapper. ``` Provide Feedback # core file ## core file **This is an abbreviation for SNOMED CT core file.** ## SNOMED CT core file A distribution file used to represent the main SNOMED CT components (concepts, descriptions and relationships). #### Notes * Previously, the term *core* was also used to refer to the content of the SNOMED CT International Release, but this usage is deprecated. * The [SNOMED CT Affiliate License](http://snomed.org/license) agreement contains a specific legal definition of the term "SNOMED CT Core", which includes all content controlled, maintained and distributed by SNOMED International. ## Alternatives * **Core file** * **Core table** * **SNOMED CT core** * **SNOMED CT core table** **References** * [SNOMED CT Affiliate License](http://snomed.org/license)\*\*\ \*\* Provide Feedback # core table ## core table **This is a synonym for SNOMED CT core file.** ## SNOMED CT core file A distribution file used to represent the main SNOMED CT components (concepts, descriptions and relationships). #### Notes * Previously, the term *core* was also used to refer to the content of the SNOMED CT International Release, but this usage is deprecated. * The [SNOMED CT Affiliate License](http://snomed.org/license) agreement contains a specific legal definition of the term "SNOMED CT Core", which includes all content controlled, maintained and distributed by SNOMED International. ## Alternatives * **Core file** * **Core table** * **SNOMED CT core** * **SNOMED CT core table** **References** * [SNOMED CT Affiliate License](http://snomed.org/license)\*\*\ \*\* Provide Feedback # cross mapping ## cross mapping **This may sometimes be used to refer to mapping.** ## mapping The process of converting data from one code system, classification, or terminology to another code system, classification, or terminology. #### Notes * The *mapping* process includes the preparation and maintenance of resources used for converting data. * SNOMED CT *mapping* resources are distributed as mapping reference sets. ## Alternatives * **Cross mapping** Provide Feedback # cts2 ## CTS2 **This is an abbreviation for Common Terminology Services 2.** ## Common Terminology Services 2 An application programming interface (API) specification of the basic functional requirements used to query and access terminological content. #### Notes * *CTS2*\ \* Is an abbreviation for *Common Terminology Services 2.*\ \* Is used by healthcare software implementers.\ \* Defines the functional requirements of a set of service interfaces to allow the representation, access, and maintenance of terminology content either locally, or across a federation of terminology services nodes.\_\ \_\ \* Is specified as an API, rather than a set of data structures. This enables a wide range of terminological content to be integrated within a common framework, without the need for significant migration or revision.\ \* Was developed from the original [HL7 CTS](http://snomed.org/cts2) specification and is now a joint initiative between HL7 and the [Object Management Group (OMG)](http://www.omg.org/). ## Alternatives * **CTS2** * **HL7 CTS2** Provide Feedback --- [Next Page](/llms-full.txt/1)