the state or fact of remaining the same one or ones, as under varying aspects or conditions: The identity of the fingerprints on the gun with those on file provided evidence that he was the killer.
2.
the condition of being oneself or itself, and not another: He doubted his own identity.
3.
condition or character as to who a person or what a thing is: a case of mistaken identity.
4.
the state or fact of being the same one as described.
5.
the sense of self, providing sameness and continuity in personality over time and sometimes disturbed in mental illnesses, as schizophrenia.
6.
exact likeness in nature or qualities: an identity of interests.
7.
an instance or point of sameness or likeness: to mistake resemblances for identities.
8.
Logic. an assertion that two terms refer to the same thing.
9.
Mathematics.
a.
an equation that is valid for all values of its variables.
b.
Also called identity element, unit element, unity.an element in a set such that the element operating on any other element of the set leaves the second element unchanged.
c.
the property of a function or map such that each element is mapped into itself.
d.
the function or map itself.
10.
AustralianInformal. an interesting, famous, or eccentric resident, usually of long standing in a community.
[Origin: 1560–70; < LL identitās, equiv. to L ident(idem) repeatedly, again and again, earlier *idem et idem (idem neut. of īdem the same + et and) + -itās-ity]
The collective aspect of the set of characteristics by which a thing is definitively recognizable or known: "If the broadcast group is the financial guts of the company, the news division is its public identity"(Bill Powell).
The set of behavioral or personal characteristics by which an individual is recognizable as a member of a group.
The quality or condition of being the same as something else.
The distinct personality of an individual regarded as a persisting entity; individuality.
Information, such as an identification number, used to establish or prove a person's individuality, as in providing access to a credit account.
Mathematics
An equation that is satisfied by any number that replaces the letter for which the equation is defined.
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 Indo-European roots.]
1570, from M.Fr. identité (14c.), from L.L. (5c.) identitatem (nom. identitas) "sameness," from ident-, comb. form of L. idem (neut.) "the same" (see identical); abstracted from identidem "over and over," from phrase idem et idem. Term identity crisis first recorded 1954.
the distinct personality of an individual regarded as a persisting entity; "you can lose your identity when you join the army"
2.
the individual characteristics by which a thing or person is recognized or known; "geneticists only recently discovered the identity of the gene that causes it"; "it was too dark to determine his identity"; "she guessed the identity of his lover"
3.
an operator that leaves unchanged the element on which it operates; "the identity under numerical multiplication is 1"
4.
exact sameness; "they shared an identity of interests"
I*den"tic*al\, a. [Cf. F. identique. See Identity.]1. The same; the selfsame; the very same; not different; as, the identical person or thing. I can not remember a thing that happened a year ago, without a conviction . . . that I, the same identical person who now remember that event, did then exist. --Reid. 2. Uttering sameness or the same truth; expressing in the predicate what is given, or obviously implied, in the subject; tautological. When you say body is solid, I say that you make an identical proposition, because it is impossible to have the idea of body without that of solidity. --Fleming. Identical equation (Alg.), an equation which is true for all values of the algebraic symbols which enter into it.
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