\begin{definition}[Definition:Right Circular Cone]
A '''right circular cone''' is a cone:
:whose base is a circle
:in which there is a line perpendicular to the base through its center which passes through the apex of the cone:
:which is made by having a right-angled triangle turning along one of the sides that form the right angle.
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{{EuclidSaid}}
:''{{:Definition:Euclid's Definitions - Book XI/18 - Cone}}''
{{EuclidDefRefNocat|XI|18|Cone}}
\end{definition}