\begin{definition}[Definition:Cylinder/Base]
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{{EuclidSaid}}
:''{{Definition:Euclid's Definitions - Book XI/23 - Base of Cylinder}}''
{{EuclidDefRefNocat|XI|23|Base of Cylinder}}
In the above diagram, the '''bases''' of the cylinder $ACBEDF$ are the faces $ABC$ and $DEF$.
\end{definition}