n. pl. i·den·ti·ties
a. The condition of being a certain person or thing: What is the identity of the author of the manuscript?
b. The set of characteristics by which a person or thing is definitively recognizable or known: "The identity of the nation had ... been keenly contested in the period of nationalist opposition to Imperial rule" (Judith M. Brown).
c. The awareness that an individual or group has of being a distinct, persisting entity: "He felt more at home thousands of miles from Britain than he did in an English village four miles from his home ... Was he losing his identity?" (Robert Fallon).
a. The fact or condition of being the same as something else: The identity of the two handwriting samples was established by an expert.
b. The fact or condition of being associated or affiliated with something else: the identity between mass and energy.
3. Information, such as an identification number, used to establish or prove a person's individuality, as in providing access to a credit account.
a. An equation that is satisfied by any number that replaces the letter for which the equation is defined.
b. Identity element.
[French identité, from Old French identite, from Late Latin identitās, from Latin idem, the same (influenced by Late Latin essentitās, being, and identidem, repeatedly), from id, it; see i- in the Appendix of Indo-European roots.]
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