idempotent
EnglishEdit
EtymologyEdit
Latin roots, idem (“same”) + potent (“having power”) – literally, “having the same power”.
Coined 1870 by American mathematician Benjamin Peirce in context of algebra.^{[1]}
PronunciationEdit
AdjectiveEdit
idempotent (not comparable)
 (mathematics, computing) Said of a function: describing an action which, when performed multiple times on the same subject, has no further effect on its subject after the first time it is performed.
 A projection operator is idempotent.
 (mathematics) Said of an element of an algebraic structure with a binary operation (such as a group or semigroup): when the element operates on itself, the result is equal to itself.
 Every finite semigroup has an idempotent element.
 Every group has a unique idempotent element: namely, its identity element.
 (mathematics) Said of a binary operation: that all of the distinct elements it can operate on are idempotent (in the sense given just above).
 Since the AND logical operator is commutative, associative, and idempotent, then it distributes with respect to itself.
 (mathematics) Said of an algebraic structure: having an idempotent operation (in the sense above).
Usage notesEdit
Contrast with nullipotent, meaning has no side effects – doing it multiple times is the same as doing it zero times, rather than once, as in idempotent.
Related termsEdit
Coordinate termsEdit
TranslationsEdit
mathematics: an action which, when performed multiple time, has no further effect on its subject after the first time it is performed


mathematics: Said of an element of an algebraic structure with a binary operation: that when the element operates on itself, the result is equal to itself


Said of a binary operation: that all of the distinct elements it can operate on are idempotent
NounEdit
idempotent (plural idempotents)
 (mathematics) An idempotent element.
 (mathematics) An idempotent structure.
ReferencesEdit
 ^ Polcino & Sehgal (2002), p. 127
 “idempotent” at FOLDOC