Is there a name for functions that are their own inverses

There are terms for various kinds of functions (or operators) such as...

associative - (a # b) # c  =  a # (b # c)
commutative - a # b  =  b # a
idempotent  - f (f (x)) = f (x)


Is there a similar name for functions that are their own inverse?

f (f (x)) = x

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