This page is part of the US Core (v1.0.0: STU1) based on FHIR R3. The current version which supercedes this version is 5.0.1. For a full list of available versions, see the Directory of published versions
<StructureDefinition xmlns="http://hl7.org/fhir"> <id value="us-core-race"/> <text> <status value="generated"/> <div xmlns="http://www.w3.org/1999/xhtml"><p><b>Generated Narrative with Details</b></p><p><b>url</b>: <a href="http://hl7.org/fhir/us/core/StructureDefinition/us-core-race">http://hl7.org/fhir/us/core/StructureDefinition/us-core-race</a></p><p><b>version</b>: 1.0.0</p><p><b>name</b>: US Core Race Extension</p><p><b>title</b>: US Core Race Extension</p><p><b>status</b>: DRAFT</p><p><b>date</b>: 01/08/2016</p><p><b>publisher</b>: HL7 US Realm Steering Committee</p><p><b>contact</b>: </p><p><b>description</b>: Concepts classifying the person into a named category of humans sharing common history, traits, geographical origin or nationality. The race codes used to represent these concepts are based upon the [CDC Race and Ethnicity Code Set Version 1.0](http://www.cdc.gov/phin/resources/vocabulary/index.html) which includes over 900 concepts for representing race and ethnicity of which 921 reference race. The race concepts are grouped by and pre-mapped to the 5 OMB race categories: - American Indian or Alaska Native - Asian - Black or African American - Native Hawaiian or Other Pacific Islander - White.</p><p><b>url</b>: <a href="http://hl7.org/fhir/us/core/StructureDefinition/us-core-race">http://hl7.org/fhir/us/core/StructureDefinition/us-core-race</a></p><p><b>version</b>: 1.0.0</p><p><b>name</b>: US Core Race Extension</p><p><b>title</b>: US Core Race Extension</p><p><b>status</b>: DRAFT</p><p><b>date</b>: 01/08/2016</p><p><b>publisher</b>: HL7 US Realm Steering Committee</p><p><b>contact</b>: </p><p><b>description</b>: Concepts classifying the person into a named category of humans sharing common history, traits, geographical origin or nationality. The race codes used to represent these concepts are based upon the [CDC Race and Ethnicity Code Set Version 1.0](http://www.cdc.gov/phin/resources/vocabulary/index.html) which includes over 900 concepts for representing race and ethnicity of which 921 reference race. The race concepts are grouped by and pre-mapped to the 5 OMB race categories: - American Indian or Alaska Native - Asian - Black or African American - Native Hawaiian or Other Pacific Islander - White.</p><p><b>purpose</b>: Complies with 2015 Edition Common Clinical Data Set for patient race.</p><p><b>fhirVersion</b>: 3.0.0</p><h3>Mappings</h3><table class="grid"><tr><td>-</td><td><b>Identity</b></td><td><b>Uri</b></td><td><b>Name</b></td></tr><tr><td>*</td><td>rim</td><td><a href="http://hl7.org/v3">http://hl7.org/v3</a></td><td>RIM Mapping</td></tr></table><p><b>kind</b>: COMPLEXTYPE</p><p><b>abstract</b>: false</p><p><b>contextType</b>: RESOURCE</p><p><b>context</b>: Patient</p><p><b>type</b>: Extension</p><p><b>baseDefinition</b>: <a href="http://hl7.org/fhir/StructureDefinition/Extension">http://hl7.org/fhir/StructureDefinition/Extension</a></p><p><b>derivation</b>: CONSTRAINT</p><h3>Snapshots</h3><table class="grid"><tr><td>-</td><td><b>Element</b></td></tr><tr><td>*</td><td>todo-bundle</td></tr></table><h3>Differentials</h3><table class="grid"><tr><td>-</td><td><b>Element</b></td></tr><tr><td>*</td><td>todo-bundle</td></tr></table></div> </text> <url value="http://hl7.org/fhir/us/core/StructureDefinition/us-core-race"/> <version value="1.0.0"/> <name value="US Core Race Extension"/> <title value="US Core Race Extension"/> <status value="draft"/> <date value="2016-08-01"/> <publisher value="HL7 US Realm Steering Committee"/> <contact> <telecom> <system value="url"/> <value value="http://www.healthit.gov"/> </telecom> </contact> <description value="Concepts classifying the person into a named category of humans sharing common history, traits, geographical origin or nationality. The race codes used to represent these concepts are based upon the [CDC Race and Ethnicity Code Set Version 1.0](http://www.cdc.gov/phin/resources/vocabulary/index.html) which includes over 900 concepts for representing race and ethnicity of which 921 reference race. The race concepts are grouped by and pre-mapped to the 5 OMB race categories: - American Indian or Alaska Native - Asian - Black or African American - Native Hawaiian or Other Pacific Islander - White."/> <purpose value="Complies with 2015 Edition Common Clinical Data Set for patient race."/> <fhirVersion value="3.0.0"/> <mapping> <identity value="rim"/> <uri value="http://hl7.org/v3"/> <name value="RIM Mapping"/> </mapping> <kind value="complex-type"/> <abstract value="false"/> <contextType value="resource"/> <context value="Patient"/> <type value="Extension"/> <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension"/> <derivation value="constraint"/> <snapshot> <element id="Extension:race"> <path value="Extension"/> <sliceName value="race"/> <short value="US Core Race Extension"/> <definition value="Concepts classifying the person into a named category of humans sharing common history, traits, geographical origin or nationality. The race codes used to represent these concepts are based upon the [CDC Race and Ethnicity Code Set Version 1.0](http://www.cdc.gov/phin/resources/vocabulary/index.html) which includes over 900 concepts for representing race and ethnicity of which 921 reference race. The race concepts are grouped by and pre-mapped to the 5 OMB race categories: - American Indian or Alaska Native - Asian - Black or African American - Native Hawaiian or Other Pacific Islander - White."/> <min value="0"/> <max value="1"/> <base> <path value="Extension"/> <min value="0"/> <max value="*"/> </base> <condition value="ele-1"/> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="children().count() > id.count()"/> <xpath value="@value|f:*|h:div"/> <source value="Element"/> </constraint> <constraint> <key value="ext-1"/> <severity value="error"/> <human value="Must have either extensions or value[x], not both"/> <expression value="extension.exists() != value.exists()"/> <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])"/> <source value="Extension"/> </constraint> <isModifier value="false"/> </element> <element id="Extension:race.id"> <path value="Extension.id"/> <representation value="xmlAttr"/> <short value="xml:id (or equivalent in JSON)"/> <definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/> <min value="0"/> <max value="1"/> <base> <path value="Element.id"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension"> <path value="Extension.extension"/> <slicing id="1"> <discriminator> <type value="value"/> <path value="url"/> </discriminator> <ordered value="false"/> <rules value="open"/> </slicing> <short value="Extension"/> <definition value="An Extension"/> <min value="0"/> <max value="*"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> </element> <element id="Extension:race.extension:ombcategory"> <path value="Extension.extension"/> <sliceName value="ombCategory"/> <short value="American Indian or Alaska Native|Asian|Black or African American|Native Hawaiian or Other Pacific Islander|White"/> <definition value="The 5 race category codes according to the [OMB Standards for Maintaining, Collecting, and Presenting Federal Data on Race and Ethnicity, Statistical Policy Directive No. 15, as revised, October 30, 1997](https://www.whitehouse.gov/omb/fedreg_1997standards)."/> <min value="0"/> <max value="5"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <mustSupport value="true"/> <isModifier value="false"/> <mapping> <identity value="iso11179"/> <map value="/ClinicalDocument/recordTarget/patientRole/patient/raceCode"/> </mapping> </element> <element id="Extension:race.extension:ombcategory.id"> <path value="Extension.extension.id"/> <representation value="xmlAttr"/> <short value="xml:id (or equivalent in JSON)"/> <definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/> <min value="0"/> <max value="1"/> <base> <path value="Element.id"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:ombcategory.extension"> <path value="Extension.extension.extension"/> <short value="Additional Content defined by implementations"/> <definition value="May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension."/> <comment value="There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone."/> <alias value="extensions"/> <alias value="user content"/> <min value="0"/> <max value="0"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:ombcategory.url"> <path value="Extension.extension.url"/> <representation value="xmlAttr"/> <short value="identifies the meaning of the extension"/> <definition value="Source of the definition for the extension code - a logical name or a URL."/> <comment value="The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.url"/> <min value="1"/> <max value="1"/> </base> <type> <code value="uri"/> </type> <fixedUri value="ombCategory"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.extension:ombcategory.valueCoding"> <path value="Extension.extension.valueCoding"/> <short value="Value of extension"/> <definition value="Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list)."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.value[x]"/> <min value="0"/> <max value="1"/> </base> <type> <code value="Coding"/> </type> <binding> <strength value="required"/> <description value="The 5 race category codes according to the [OMB Standards for Maintaining, Collecting, and Presenting Federal Data on Race and Ethnicity, Statistical Policy Directive No. 15, as revised, October 30, 1997](https://www.whitehouse.gov/omb/fedreg_1997standards)."/> <valueSetReference> <reference value="http://hl7.org/fhir/us/core/ValueSet/omb-race-category"/> </valueSetReference> </binding> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.extension:detailed"> <path value="Extension.extension"/> <sliceName value="detailed"/> <short value="Extended race codes"/> <definition value="The 900+ CDC race codes that are grouped under one of the 5 OMB race category codes:."/> <min value="0"/> <max value="*"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <isModifier value="false"/> <mapping> <identity value="iso11179"/> <map value="/ClinicalDocument/recordTarget/patientRole/patient/sdtc:raceCode"/> </mapping> </element> <element id="Extension:race.extension:detailed.id"> <path value="Extension.extension.id"/> <representation value="xmlAttr"/> <short value="xml:id (or equivalent in JSON)"/> <definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/> <min value="0"/> <max value="1"/> <base> <path value="Element.id"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:detailed.extension"> <path value="Extension.extension.extension"/> <short value="Additional Content defined by implementations"/> <definition value="May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension."/> <comment value="There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone."/> <alias value="extensions"/> <alias value="user content"/> <min value="0"/> <max value="0"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:detailed.url"> <path value="Extension.extension.url"/> <representation value="xmlAttr"/> <short value="identifies the meaning of the extension"/> <definition value="Source of the definition for the extension code - a logical name or a URL."/> <comment value="The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.url"/> <min value="1"/> <max value="1"/> </base> <type> <code value="uri"/> </type> <fixedUri value="detailed"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.extension:detailed.valueCoding"> <path value="Extension.extension.valueCoding"/> <short value="Value of extension"/> <definition value="Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list)."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.value[x]"/> <min value="0"/> <max value="1"/> </base> <type> <code value="Coding"/> </type> <binding> <strength value="required"/> <description value="The [900+ CDC Race codes](http://www.cdc.gov/phin/resources/vocabulary/index.html) that are grouped under one of the 5 OMB race category codes."/> <valueSetReference> <reference value="http://hl7.org/fhir/us/core/ValueSet/detailed-race"/> </valueSetReference> </binding> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.extension:text"> <path value="Extension.extension"/> <sliceName value="text"/> <short value="Race Text"/> <definition value="Plain text representation of the race concept(s)."/> <min value="1"/> <max value="1"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <mustSupport value="true"/> <isModifier value="false"/> </element> <element id="Extension:race.extension:text.id"> <path value="Extension.extension.id"/> <representation value="xmlAttr"/> <short value="xml:id (or equivalent in JSON)"/> <definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/> <min value="0"/> <max value="1"/> <base> <path value="Element.id"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:text.extension"> <path value="Extension.extension.extension"/> <short value="Additional Content defined by implementations"/> <definition value="May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension."/> <comment value="There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone."/> <alias value="extensions"/> <alias value="user content"/> <min value="0"/> <max value="0"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Extension:race.extension:text.url"> <path value="Extension.extension.url"/> <representation value="xmlAttr"/> <short value="identifies the meaning of the extension"/> <definition value="Source of the definition for the extension code - a logical name or a URL."/> <comment value="The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.url"/> <min value="1"/> <max value="1"/> </base> <type> <code value="uri"/> </type> <fixedUri value="text"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.extension:text.valueString"> <path value="Extension.extension.valueString"/> <short value="Value of extension"/> <definition value="Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list)."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.value[x]"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.url"> <path value="Extension.url"/> <representation value="xmlAttr"/> <short value="identifies the meaning of the extension"/> <definition value="Source of the definition for the extension code - a logical name or a URL."/> <comment value="The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension."/> <min value="1"/> <max value="1"/> <base> <path value="Extension.url"/> <min value="1"/> <max value="1"/> </base> <type> <code value="uri"/> </type> <fixedUri value="http://hl7.org/fhir/us/core/StructureDefinition/us-core-race"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Extension:race.value[x]"> <path value="Extension.value[x]"/> <short value="Value of extension"/> <definition value="Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list)."/> <min value="0"/> <max value="0"/> <base> <path value="Extension.value[x]"/> <min value="0"/> <max value="1"/> </base> <type> <code value="base64Binary"/> </type> <type> <code value="boolean"/> </type> <type> <code value="code"/> </type> <type> <code value="date"/> </type> <type> <code value="dateTime"/> </type> <type> <code value="decimal"/> </type> <type> <code value="id"/> </type> <type> <code value="instant"/> </type> <type> <code value="integer"/> </type> <type> <code value="markdown"/> </type> <type> <code value="oid"/> </type> <type> <code value="positiveInt"/> </type> <type> <code value="string"/> </type> <type> <code value="time"/> </type> <type> <code value="unsignedInt"/> </type> <type> <code value="uri"/> </type> <type> <code value="Address"/> </type> <type> <code value="Age"/> </type> <type> <code value="Annotation"/> </type> <type> <code value="Attachment"/> </type> <type> <code value="CodeableConcept"/> </type> <type> <code value="Coding"/> </type> <type> <code value="ContactPoint"/> </type> <type> <code value="Count"/> </type> <type> <code value="Distance"/> </type> <type> <code value="Duration"/> </type> <type> <code value="HumanName"/> </type> <type> <code value="Identifier"/> </type> <type> <code value="Money"/> </type> <type> <code value="Period"/> </type> <type> <code value="Quantity"/> </type> <type> <code value="Range"/> </type> <type> <code value="Ratio"/> </type> <type> <code value="Reference"/> </type> <type> <code value="SampledData"/> </type> <type> <code value="Signature"/> </type> <type> <code value="Timing"/> </type> <type> <code value="Meta"/> </type> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> </snapshot> <differential> <element id="Extension:race"> <path value="Extension"/> <sliceName value="race"/> <short value="US Core Race Extension"/> <definition value="Concepts classifying the person into a named category of humans sharing common history, traits, geographical origin or nationality. The race codes used to represent these concepts are based upon the [CDC Race and Ethnicity Code Set Version 1.0](http://www.cdc.gov/phin/resources/vocabulary/index.html) which includes over 900 concepts for representing race and ethnicity of which 921 reference race. The race concepts are grouped by and pre-mapped to the 5 OMB race categories: - American Indian or Alaska Native - Asian - Black or African American - Native Hawaiian or Other Pacific Islander - White."/> <min value="0"/> <max value="1"/> <isModifier value="false"/> </element> <element id="Extension:race.extension:ombcategory"> <path value="Extension.extension"/> <sliceName value="ombCategory"/> <short value="American Indian or Alaska Native|Asian|Black or African American|Native Hawaiian or Other Pacific Islander|White"/> <definition value="The 5 race category codes according to the [OMB Standards for Maintaining, Collecting, and Presenting Federal Data on Race and Ethnicity, Statistical Policy Directive No. 15, as revised, October 30, 1997](https://www.whitehouse.gov/omb/fedreg_1997standards)."/> <min value="0"/> <max value="5"/> <type> <code value="Extension"/> </type> <mustSupport value="true"/> <isModifier value="false"/> <mapping> <identity value="iso11179"/> <map value="/ClinicalDocument/recordTarget/patientRole/patient/raceCode"/> </mapping> </element> <element id="Extension:race.extension:ombcategory.url"> <path value="Extension.extension.url"/> <min value="1"/> <max value="1"/> <type> <code value="uri"/> </type> <fixedUri value="ombCategory"/> </element> <element id="Extension:race.extension:ombcategory.valueCoding"> <path value="Extension.extension.valueCoding"/> <min value="1"/> <max value="1"/> <type> <code value="Coding"/> </type> <binding> <strength value="required"/> <description value="The 5 race category codes according to the [OMB Standards for Maintaining, Collecting, and Presenting Federal Data on Race and Ethnicity, Statistical Policy Directive No. 15, as revised, October 30, 1997](https://www.whitehouse.gov/omb/fedreg_1997standards)."/> <valueSetReference> <reference value="http://hl7.org/fhir/us/core/ValueSet/omb-race-category"/> </valueSetReference> </binding> </element> <element id="Extension:race.extension:detailed"> <path value="Extension.extension"/> <sliceName value="detailed"/> <short value="Extended race codes"/> <definition value="The 900+ CDC race codes that are grouped under one of the 5 OMB race category codes:."/> <min value="0"/> <max value="*"/> <type> <code value="Extension"/> </type> <isModifier value="false"/> <mapping> <identity value="iso11179"/> <map value="/ClinicalDocument/recordTarget/patientRole/patient/sdtc:raceCode"/> </mapping> </element> <element id="Extension:race.extension:detailed.url"> <path value="Extension.extension.url"/> <min value="1"/> <max value="1"/> <type> <code value="uri"/> </type> <fixedUri value="detailed"/> </element> <element id="Extension:race.extension:detailed.valueCoding"> <path value="Extension.extension.valueCoding"/> <min value="1"/> <max value="1"/> <type> <code value="Coding"/> </type> <binding> <strength value="required"/> <description value="The [900+ CDC Race codes](http://www.cdc.gov/phin/resources/vocabulary/index.html) that are grouped under one of the 5 OMB race category codes."/> <valueSetReference> <reference value="http://hl7.org/fhir/us/core/ValueSet/detailed-race"/> </valueSetReference> </binding> </element> <element id="Extension:race.extension:text"> <path value="Extension.extension"/> <sliceName value="text"/> <short value="Race Text"/> <definition value="Plain text representation of the race concept(s)."/> <min value="1"/> <max value="1"/> <type> <code value="Extension"/> </type> <mustSupport value="true"/> <isModifier value="false"/> </element> <element id="Extension:race.extension:text.url"> <path value="Extension.extension.url"/> <min value="1"/> <max value="1"/> <type> <code value="uri"/> </type> <fixedUri value="text"/> </element> <element id="Extension:race.extension:text.valueString"> <path value="Extension.extension.valueString"/> <min value="1"/> <max value="1"/> <type> <code value="string"/> </type> </element> <element id="Extension:race.url"> <path value="Extension.url"/> <min value="1"/> <max value="1"/> <fixedUri value="http://hl7.org/fhir/us/core/StructureDefinition/us-core-race"/> </element> </differential> </StructureDefinition>