Definition:Pyramid/Apex

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Definition

Pyramid.png


The vertex of a pyramid which is the common vertex of its triangular faces is called the apex of the pyramid.

In the above diagram, $Q$ is the apex.


Also known as

The apex of a pyramid is seen in some sources (for example Euclid's The Elements) as vertex.


Also see


Linguistic Note

The plural of apex is apices, which is pronounced ay-pi-seez.

The form apexes can often be seen, but this is technically incorrect.

Compare vertex.


Hence the colloquial phrase base over apex as the description of a particularly flamboyant physical tumble.