Definition:Coslice Category

Definition
Let $\mathbf C$ be a metacategory.

Let $C \in \mathbf C_0$ be an object of $\mathbf C$.

The coslice category of $\mathbf C$ under $C$, denoted $C / \mathbf C$, is defined as follows:

By Coslice Category is Category, this is indeed a category.

Also see

 * Slice Category