Definition:Involution (Mapping)

Definition
An involution is a mapping which is its own inverse.

That is, if $f: A \to A$ is an involution, then:


 * $\forall x \in A: f \left({f \left({x}\right)}\right) = x$

Also known as
An involution is also known as an involutive mapping or an involutive function.

Also see
As a mapping is also by definition a relation, the concept of an involutive relation can also be defined.

However, it is of little value to do so, as from an [Involutive Relation is Bijective and Symmetric, such a relation is a mapping by default.