modular arithmetic

noun1

1. •
   Any system of arithmetic for integers which, for some given positive integer n, is equivalent to the set of integers being mapped onto the finite set {0, ... n} according to congruence modulo n, and in which addition and multiplication are defined consistently with the results of ordinary arithmetic being so mapped.

   • Hence for prime moduli, modular arithmetic is very similar to regular rational arithmetic with all four operations defined. — 1997