What does "permutation" mean?

Permutation: (Math.) (a) 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, n., 4. (b) Any one of such possible arrangements.

Additional senses

  1. 2.(Law) 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.

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