idempotent

1. (mathematics, computing) (said of a function) Such that, when performed multiple times on the same subject, it has no further effect on its subject after the first time it is performed.Examples: "A projection operator is idempotent."; "An HTTP request using the PUT verb should be idempotent, so that it can be sent to the server any number of times with the same end result."not-comparable

2. (mathematics) (said of an element of an algebraic structure with a binary operation, such as a group or semigroup) Such that, when it operates on itself, the result is equal to itself.Examples: "Every finite semigroup has an idempotent element."; "Every group has a unique idempotent element: namely, its identity element."not-comparable

3. (mathematics) (said of a binary operation) Such that all of the distinct elements it can operate on are idempotent (in the sense given just above).Examples: "Since the AND logical operator is commutative, associative, and idempotent, it distributes with respect to itself."not-comparable

4. (mathematics) (said of an algebraic structure) Having an idempotent operation (in the sense given above).not-comparable