Definition:Polynomial Congruence/Solution

Definition
Let:
 * $P \left({x}\right) \equiv 0 \pmod n$

be a polynomial congruence.

A solution of $P \left({x}\right) \equiv 0 \pmod n$ is a residue class modulo $n$ such that any element of that class satisfies the congruence.

Also see

 * Solutions of Polynomial Congruences: if one such element of a residue class satisfies the congruence, they all do.