Толковый словарь английского языка Oxford English Reference - identity

n. (pl. -ies) 1 a the quality or condition of being a specified person or thing. b individuality, personality (felt he had lost his identity). 2 identification or the result of it (a case of mistaken identity; identity card). 3 the state of being the same in substance, nature, qualities, etc.; absolute sameness (no identity of interests between them). 4 Algebra a the equality of two expressions for all values of the quantities expressed by letters. b an equation expressing this, e.g. (x + 1)(2) = x(2) + 2x + 1. 5 Math. a (in full identity element) an element in a set, left unchanged by any operation to it. b a transformation that leaves an object unchanged. Phrases and idioms identity crisis a phase in which an individual feels a need to establish an identity in relation to society. identity parade = identification parade. Etymology: LL identitas f. L idem same