• synonyms


noun Geometry.
  1. a perpendicular from the center of a regular polygon to one of its sides.
Show More

Origin of apothem

1855–60; < French apothème, probably on the model of Greek hypóthēma base; see apo-, theme
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for apothem

Historical Examples

  • The "Apothem is a perpendicular from the vertex of a pyramid on a side of the base."

    The Solution of the Pyramid Problem

    Robert Ballard

  • A peculiarity of this pyramid is, that base is to altitude as apothem is to half base.

  • In any pyramid, the apothem is to half the base as the area of the four sides is to the area of the base.

  • I have mentioned the above to show how very nearly these ratios agree with my exact ratio of 21 to 34 half base to apothem.

British Dictionary definitions for apothem


  1. the perpendicular line or distance from the centre of a regular polygon to any of its sides
Show More

Word Origin

C20: from apo- + Greek thema, from tithenai to place
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012