\begin{definition}[Definition:Isolated Zero]
Let $f: \C \to \C$ be a complex function.
Let $\map f {z_0} = 0$ for some $z_0 \in \C$. 
We say $z_0$ is an '''isolated zero''' of $f$ if there exists an open ball $B$ containing $z_0$, such that $\map f w \ne 0$ for all $w \in B \setminus \set {z_0}$.
 
Category:Definitions/Complex Analysis
\end{definition}