(philosophy) The principle that if two objects are absolutely identical then they must be indistinguishable from one another with respect to all of their properties.

plural of identity card

(psychology) A person's internal sense of self as belonging to a particular gender or genders, or to no gender.

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.

(mathematics, of a function) Being equal to the zero function and not merely zero at a particular point in its domain.

plural of identity crisis

Alternative form of nonidentical

Alternative form of nonidentical

plural of identity function