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DHS Lexicon


The DHS Lexicon is a unified controlled vocabulary that DHS and its Components use when communicating and sharing data.  It was created by combining and standardizing the different vocabularies used by the Department.  By providing a common definition for the terms used every day, the Lexicon reduces the possibility of misunderstandings when communicating across the Department and helps DHS to develop and manage knowledge, information, and data.  The DHS Lexicon is the official source for terms and definitions supporting the Department and the homeland security community.

The DHS Lexicon definitions is provided via three attributes:

Definition – A statement of the meaning of a particular word or phrase.  In its construction, a definition will always state the main object or root meaning first, followed by appropriate modification if necessary.

Extended Definition – If the term expresses a highly complex thought, a further explanatory statement or more detail may be required.  An extended definition provides this supplemental information without repeating or contradicting the definition.  Instead, it provides additional statements of fact further clarifying the definition, such as:

  • Identification of distinguishing characteristics;
  • Supporting facts or information; and
  • What is included or not included in the definition.

Annotation – An annotation is not considered part of the definition.  Where necessary, an annotation provides additional comment or notation about the definition.  For example, annotations can provide examples of the use of the definition, offer deeper elaboration, or cite legal use or interpretation.

Attachment Ext. Size Date
DHS Lexicon PDF 7.35 MB 01/16/2018
Last Updated: 06/08/2022
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