Definition of apothem in English:

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Pronunciation: /ˈapəˌTHem/


A line from the center of a regular polygon at right angles to any of its sides.
Example sentences
  • Given a circle, the apothem is the perpendicular distance from the midpoint of a chord to the circle's center.
  • Once the perimeter and the apothem are known, the formula relating the two to area can be used to solve for the area.
  • For a polygon of n sides, there are n possible apothems, all the same length of course.


Late 19th century: from Greek apotithenai 'put aside, deposit', from apo 'away' + tithenai 'to place'.

For editors and proofreaders

Syllabification: ap·o·them

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