octagon
Americannoun
noun
Etymology
Origin of octagon
1650–60; < Latin octagōnon < Greek oktágōnon, noun use of neuter of oktágōnos octangular; see octa-, -gon
Explanation
An octagon is a shape with eight sides. Picture a stop sign, and you'll get the idea. If your house is a strange, roundish shape with eight walls, it's an octagon, and if your medal for being the most improved bowler in your league has a shape with eight equal sides, it's also an octagon. You'll come across the word most often in geometry class, where you'll also learn that an octagon's eight interior angles always add up to 1080 degrees. The Greek root is oktagononos, "eight-angled," from okto, "eight," and gonia, "angle."
Vocabulary lists containing octagon
Geometry - Introductory
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UCPS 6th Grade Roots List #6
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Geometry (Base List)
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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.
Bouts take place in an eight-sided ring -- dubbed "The Octagon" -- bounded by a chainlink fence.
From Barron's • Mar. 8, 2026
Interpublic Group bought Advantage in 1997 and renamed it Octagon.
From The Wall Street Journal • Jan. 21, 2026
Gleyber Torres, 28, 2B, Octagon: Torres found new life after moving to leadoff in late August, posting an OPS of .856 down the stretch and into the postseason for the Yankees.
From Los Angeles Times • Oct. 31, 2024
Tracie Ross added: "The Octagon theatre's one of a kind and he's one of a kind, and getting money back into the arts and getting people back into live theatre is amazing."
From BBC • Dec. 10, 2023
As those conversations took place, the one thing that stood out for my parents and me was the personal connection I felt with the agent I ultimately chose, Janey Miller from Octagon.
From "Courage to Soar" by Simone Biles
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
