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[ok-tuh-gon, -guh n] /ˈɒk təˌgɒn, -gən/
a polygon having eight angles and eight sides.
Also called octangle.
Origin of octagon
1650-60; < Latin octagōnon < Greek oktágōnon, noun use of neuter of oktágōnos octangular; see octa-, -gon Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for octagon
Contemporary Examples
Historical Examples
  • It was in the shape of an octagon, and the turns were considered very safe.

  • In the application of the dome to the octagon no pendentives are employed.

    Byzantine Churches in Constantinople Alexander Van Millingen
  • The plan of the octagon included in its area one bay on each of its four sides.

    Ely Cathedral Anonymous
  • The stone-work of the octagon must be completed by the restoration of the pinnacles and parapet.

    Ely Cathedral Anonymous
  • The fourth large window in the octagon has been filled with painted glass.

    Ely Cathedral Anonymous
  • In this octagon the High Council held most of their meetings.

    The Story of the Mormons William Alexander Linn
  • The place was an octagon, surrounded on all sides by public buildings.

    Up The Baltic Oliver Optic
  • The sides of the octagon are equal, and the alternate angles coincident.

    The Prehistoric World E. A. Allen
  • The octagon is not quite regular, but the sides are very nearly equal.

    The Prehistoric World E. A. Allen
British Dictionary definitions for octagon


a polygon having eight sides
Word Origin
C17: via Latin from Greek oktagōnos, having eight angles
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
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Word Origin and History for octagon

1650s, from Latin octagonos, from Greek oktagononos, literally "eight-angled," from okta- comb. form of okto "eight" (see eight) + gonia "angle," related to gony "knee" (see knee (n.)). Also octogon (1650s), from French octogone.

Online Etymology Dictionary, © 2010 Douglas Harper
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octagon in Science
A polygon having eight sides.

octagonal adjective (ŏk-tāg'ə-nəl)
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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octagon in Culture

octagon definition

A polygon having eight sides.

The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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