(set theory) A mathematical operation that returns a set taking one or more sets as input.

Alternative spelling of set theoretically

(mathematics) In a manner which uses set theory / (mathematics) In the sense of set theory

(set theory) A set that is countable.

(fuzzy set theory, fuzzy logic) A set whose elements have degrees of membership, instead of only full and empty membership.

(tennis, of a victory or a loss in a match) Achieved in the minimal possible number of sets.

plural of power set

Alternative form of setlist

(UK) A flat triangular piece of plastic or other material, having corners of precise angles, used in technical drawing

(transitive) To release, to free, to give freedom to.