1. The act of permuting; exchange of the thing for another; mutual transference; interchange. The violent convulsions and permutations that have been made in property. (Burke)
2. (Science: mathematics) The arrangement of any determinate number of things, as units, objects, letters, etc, in all possible orders, one after the other; called also alternation. Cf. Combination. Any one of such possible arrangements.
3. Barter; exchange. Permutation lock, a lock in which the parts can be transposed or shifted, so as to require different arrangements of the tumblers on different occasions of unlocking.
Origin: L. Permutatio: cf. F. Permutation. See Permute.