The first moment of existence of a thing, whether living or not. The concept of the big bang theory, at the instant it happened, represents the instantiation of the universe.

Table instance (or database instance), a concept in database design; see Row (database)

Instantiation principle - the idea that if properties exist, the essence that "has" the properties must necessarily exist

A concept in Platonism, see idea

Universal instantiation and existential instantiation, two rules of inference in logic

Instantiation (computer science), A concept in object-oriented programming; see Object (computer science), object lifetime

Instance dungeon, a feature of many online games such as World of Warcraft and City of Heroes.