types are identified by that are subtypes of the metadata concept . Individual reference sets of a particular type are identified and named by concepts that are  of the concept that identifies the reference set type.


Reference Set Types in the Metadata Hierarchy (2018-01-31)


 900000000000455006 |Reference set|
     900000000000516008 |Annotation type|
     900000000000521006 |Association type|
     900000000000480006 |Attribute value type|
     705109006 |Code to expression type reference set|
     447250001 |Complex map type reference set|
     609430003 |Concept model reference set|
     900000000000538005 |Description format|
     733614007 |Expansion history reference set|
     609331003 |Extended map type reference set|
     733613001 |Intensional definition reference set|
     900000000000506000 |Language type|
     705111002 |Map correlation and origin type reference set|
     900000000000534007 |Module dependency|
     723564002 |MRCM reference set|
     733618005 |Ordered association type reference set|
     733619002 |Ordered component type reference set|
     447258008 |Ordered type reference set|
     900000000000512005 |Query specification type|
     900000000000456007 |Reference set descriptor|
     900000000000496009 |Simple map|
     446609009 |Simple type reference set|



Other concepts within the metadata hierarchy are used to name additional attributes within particular types of reference sets and to provide values for those attributes.

Reference Set Attributes in Metadata Hierarchy (2018-01-31) (some omitted)


 900000000000457003 |Reference set attribute|
     447257003 |"Linked to" reference set attribute|
     900000000000511003 |Acceptability|
     900000000000518009 |Annotated component|
     900000000000519001 |Annotation|
     900000000000532006 |Association source component|
     900000000000533001 |Association target component|
     900000000000458008 |Attribute description|
     900000000000479008 |Attribute order|
     723576002 |Attribute rule|
     900000000000459000 |Attribute type|
     900000000000491004 |Attribute value|
     733616009 |Authoring substrate|
     723571007 |Cardinality|
     609431004 |Concept model domain|
     609432006 |Concept model range|
     609642003 |Concept model relationship type|
     723573005 |Concept model rule strength|
     723574004 |Content type|
     900000000000535008 |Dependency target|
     900000000000539002 |Description format|
     900000000000510002 |Description in dialect|
     900000000000544009 |Description length|
     723565001 |Domain constraint|
     733612006 |Expansion substrate|
     706999006 |Expression|
     900000000000514006 |Generated reference set|
     723572000 |Grouped|
     723570008 |Guide URL|
     900000000000504002 |Map advice|
     609330002 |Map category value|
     900000000000501005 |Map group|
     900000000000502003 |Map priority|
     900000000000503008 |Map rule|
     900000000000500006 |Map source concept|
     900000000000505001 |Map target|
     723577006 |MRCM rule reference set|
     705116007 |Original code system source for linked content value|
     723566000 |Parent domain|
     447255006 |Priority order reference set attribute|
     723567009 |Proximal primitive constraint|
     723568004 |Proximal primitive refinement|
     900000000000515007 |Query|
     733615008 |Query language|
     733617000 |Query string|
     723575003 |Range constraint|
     ... more attributes ...