(group theory) A binary map in a given group G, given by [g, h] = ghg−1h−1, where g and h are elements of G, which yields the group's identity if and only if the group operation commutes for g and h.
(ring theory) A binary map in a given ring R, given by [a, b] = ab − ba, where a and b are elements of R, which yields the ring's zeroelement if and only if the multiplication operation commutes for a and b.
“A Short 330 twin-turboprop commuterliner is another impressive exhibit which in due course will be opened to the public - including wheelchair access.”
commutant
(logic) The subset of all elements of a semigroup that commute with the elements of a given subset