Beamer: reformat title text in definition block

I am using the Monterey theme in Beamer which displays definition block titles as

Definition (My Definition)

I would like to change that to

Definition: My Definition

\documentclass{beamer}  
\usetheme{Monterey}

\begin{document}
    
    
\begin{frame}
    \begin{definition}[My Definition]
        A definition
    \end{definition}
\end{frame}

\end{document}