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.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.
American Heritage Dictionary Products
The American Heritage Dictionary, 5th Edition
The American Heritage Dictionary of Idioms
The American Heritage Roget's Thesaurus
Curious George's Dictionary
The American Heritage Children's Dictionary
The American Heritage Dictionary of Indo-European Roots
The American Heritage Student Grammar Dictionary
The American Heritage Desk Dictionary + Thesaurus
The American Heritage Science Dictionary
The American Heritage Dictionary of Business Terms
The American Heritage Student Dictionary
The American Heritage Essential Student Thesaurus