\begin{definition}[Definition:Secant Function/Complex]
Let $z \in \C$ be a complex number.
The complex function $\sec z$ is defined as:
:$\sec z = \dfrac 1 {\cos z}$
where $\cos z$ is the cosine of $z$.
The definition is valid for all $z \in \C$ such that $\cos z \ne 0$.
Category:Definitions/Secant Function
\end{definition}