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Synonyms

octagonal

American  
[ok-tag-uh-nl] / ɒkˈtæg ə nl /

adjective

  1. having eight angles and eight sides.


octagonal British  
/ ɒkˈtæɡənəl /

adjective

  1. having eight sides and eight angles

  2. of or relating to an octagon

"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

Other Word Forms


Etymology

Origin of octagonal

1565–75; octagon + -al 1, replacing earlier octogonal < New Latin octōgōnālis, equivalent to octō- octo- + Greek gōn ( ía ) angle + -ālis -al 1


Explanation

Anything that's octagonal has eight sides and eight angles. A stop sign has an octagonal shape, and so may your trampoline You can also call something that's octagonal an octagon. Octagonal buildings may be unusual, but you can find examples of them around the world — there are many churches and cathedrals with octagonal sections, for example. Both octagonal and octagon come from the Greek oktagononos, "eight-angled," from the roots okto, "eight," and gonia, "angle."

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Vocabulary lists containing octagonal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The temporary arena that has been under construction is slated to feature an octagonal cage for the fights at its center, and it’s expected to fit about 4,000 guests.

From MarketWatch ● May 29, 2026

Original plans called for an octagonal building with a grand piano.

From The Wall Street Journal ● Dec. 14, 2025

The gothic building with its octagonal tower was once home to Hammer Horror Studios.

From BBC ● Oct. 30, 2025

There’s dark woodwork, octagonal pillars, curlicues of ironwork in the old-fashioned windows, carved details of garlands and flowers and urns.

From Seattle Times ● Feb. 15, 2024

Zizmo drives through the gloom, past the octagonal gazebos and the monument of the Civil War Hero, and into the woods where the Ottawa once held their summer camp.

From "Middlesex: A Novel" by Jeffrey Eugenides

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