Meaning of PERMUTATION in English
noun barter; exchange.
2. permutation ·noun any one of such possible arrangements.
3. permutation ·noun the act of permuting; exchange of the thing for another; mutual transference; interchange.
4. permutation ·noun 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, ·noun, 4.
Webster English vocab. Английский словарь Webster. 2012