Definition:Coprime/Integers/Relatively Composite

Definition
Let $a$ and $b$ be integers such that $b \ne 0$ and $a \ne 0$ (i.e. they are both non-zero).

Let $\gcd \left\{{a, b}\right\}$ be the greatest common divisor of $a$ and $b$.

If $\gcd \left\{{a, b}\right\} > 1$, then $a$ and $b$ are relatively composite.

That is, two integers are relatively composite if they are not coprime.