Table: SRDEF

FieldDescription
RT:Record Type (STY = Semantic Type or RL = Relation).
UI:Unique Identifier of the Semantic Type or Relation.
STY/RL:Name of the Semantic Type or Relation.
STN/RTN:Tree Number of the Semantic Type or Relation.
DEF:Definition of the Semantic Type or Relation.
EX:Examples of Metathesaurus concepts with this Semantic Type (STY records only).
UN:Usage note for Semantic Type assignment (STY records only).
NH:The Semantic Type and its descendants allow the non-human flag (STY records only).
ABR:Abbreviation of the Relation Name or Semantic Type.
RIN:Inverse of the Relation (RL records only).

From: 5, Semantic Network

Cover of UMLS® Reference Manual
UMLS® Reference Manual [Internet].
Bethesda (MD): National Library of Medicine (US); 2009 Sep-.

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