decagon
Americannoun
noun
Other Word Forms
- decagonal adjective
- decagonally adverb
Etymology
Origin of decagon
From the Medieval Latin word decagōnum, dating back to 1565–75. See deca-, -gon
Explanation
A decagon is a closed shape with ten sides and ten angles. Your geometry teacher would also tell you that a decagon is a polygon. The word decagon comes from Greek roots, deka, or "ten," and gōnia, "angle or corner." Any ten-sided shape can be called a decagon, whether it's a street sign or the doodle you draw in your notebook during math class. Speaking of math class, in geometry you may learn that a "regular decagon" is one with sides that are all equal to each other and with internal angles that all measure 144 degrees.
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.
Most of the list came from the state eighth grade curriculum: barometer, decagon, perpendicular .
From "Schooled" by Gordon Korman
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The plan of the church was a decagon, within which six composite columns in the centre supported six semi-circular vaults.
From Old and New London Volume I by Thornbury, Walter
Below the arches are the chapels which surround the decagon in symmetrical fashion.
From The Cathedrals and Churches of the Rhine by Mansfield, M. F. (Milburg Francisco)
The solution is required later on in the construction of a regular decagon.
From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various
The story of the Shamash shum ukin revolt is continued by Cylinder C, a decagon, whose form points to the fact that it is a fuller edition.
From Assyrian Historiography by Olmstead, A. T. (Albert Ten Eyck)
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.