\begin{definition}[Definition:Non-Archimedean/Metric]
A metric $d$ on a metric space $X$ is '''non-Archimedean''' {{iff}}:
:$\map d {x, y} \le \max \set {\map d {x, z}, \map d {y, z} }$
for all $x, y, z \in X$.
\end{definition}