Definition:Associative Operation

Definition
Let $S$ be a set.

Let $\circ : S \times S \to S$ be a binary operation.

Then $\circ$ is associative :


 * $\forall x, y, z \in S: \paren {x \circ y} \circ z = x \circ \paren {y \circ z}$

Also see

 * Definition:Semigroup
 * Associativity on Four Elements
 * General Associativity Theorem