Definition:Associative

Definition
Let $$\circ$$ be a binary operation.

Then $$\circ$$ is defined as being associative on $$S$$ iff:


 * $$\forall x, y, z \in S: \left({x \circ y}\right) \circ z = x \circ \left({y \circ z}\right)$$.

Historical Note
The term associative was coined by William Hamilton in about 1844 while thinking about octonions, which aren't.