\begin{definition}[Definition:Functor/Contravariant/Definition 2]
Let $\mathbf C$ and $\mathbf D$ be metacategories.
A '''contravariant functor''' $F : \mathbf C \to \mathbf D$ is a covariant functor:
:$F: \mathbf C^{\text{op}} \to \mathbf D$
where $\mathbf C^{\text{op}}$ is the dual category of $\mathbf C$.
\end{definition}