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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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.