ap·​o·​them ˈa-pə-ˌthem How to pronounce apothem (audio)
: the perpendicular from the center of a regular polygon to one of the sides

Word History


borrowed from French apothème, of uncertain origin

Note: The term is most likely based on a presumed Greek *apóthema or *apóthēma, a derivative of apotithénai "to put away, put aside" (perhaps taken to mean "to place to the side"), parallel to hypóthēma "base, stand," a derivative of hypotithénai "to put under" (see apothecary). It is undetermined who first used the word, which appears as apotheme in the expanded fourth edition (Paris, 1710) of the French priest and mathematician Bernard Lamy's Les elemens de geometrie (first edition 1685).

First Known Use

1813, in the meaning defined above

Time Traveler
The first known use of apothem was in 1813

Dictionary Entries Near apothem

Cite this Entry

“Apothem.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/apothem. Accessed 23 Feb. 2024.

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