Definition:Polygon/Regular/Apothem

Definition
The apothem of a regular polygon $P$ is defined as the perpendicular distance from the center of $P$ to one of its sides.


 * Apothem.png

In the above, the length of $OM$ is the apothem of the regular polygon.

Also see

 * Regular Polygon can be Circumscribed around Circle


 * Definition:Long Radius of Regular Polygon