\begin{definition}[Definition:Domain (Set Theory)/Binary Operation]
Let $\circ: S \times S \to T$ be a binary operation.
The '''domain''' of $\circ$ is the set $S$ and can be denoted $\Dom \circ$.
This definition can be considered as the same as that for the '''domain''' of a mapping, where the domain would be defined as $S \times S$.
Category:Definitions/Abstract Algebra
\end{definition}