plural of standard of identity

(US, Canada, law) A government regulation establishing the criteria which must be met before a product may be labeled as being a certain food.

plural of identity card

The deliberate assumption of another person's identity, usually to gain access to that person's finances or to frame a person for a crime.

(algebra) An element of an algebraic structure, generally denoted 1, which is an identity for a multiplicative operation (generally denoted × or *, or by concatenation).

(linear algebra) A diagonal matrix all of the diagonal elements of which are equal to 1.

(algebra) An element of an algebraic structure, generally denoted 0, which is an identity for an additive operation (generally denoted +). That is, x + 0 = 0 + x = x for any x in the structure.

(algebra) An element of a structure that produces an identity mapping when applied on the right.

(algebra) An element of a structure that produces an identity mapping when applied on the left.

(algebra) An element of an algebraic structure which when applied, in either order, to any other element via a binary operation yields the other element.