\begin{definition}[Definition:Divisor (Algebra)/Ring with Unity]
Let $\struct {R, +, \circ}$ be an ring with unity whose zero is $0_R$ and whose unity is $1_R$.
Let $x, y \in D$.
We define the term '''$x$ divides $y$ in $R$''' as follows:
:$x \mathrel {\divides_R} y \iff \exists t \in R: y = t \circ x$
When no ambiguity results, the subscript is usually dropped, and '''$x$ divides $y$ in $R$''' is just written $x \divides y$.
\end{definition}