decagon

American  

[dek-uh-gon, -guhn] / ˈdɛk əˌgɒn, -gən /

noun

Geometry.

1. a polygon having ten angles and ten sides.

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decagon British  

/ dɪˈkæɡənəl, ˈdɛkəˌɡɒn /

noun

1. a polygon having ten sides

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decagon Scientific  

/ dĕk′ə-gŏn′ /

1. A polygon having ten sides.

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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

Most of the list came from the state eighth grade curriculum: barometer, decagon, perpendicular .

From "Schooled" by Gordon Korman

If then the bisected chord be a side of the decagon, and if the radius be still 1280, the double of the lesser segment exceeds 125.

From A Budget of Paradoxes, Volume II by Smith, David Eugene

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)

To inscribe a regular decagon in a given circle.

From The Teaching of Geometry by Smith, David Eugene

The first known was Cylinder A, a decagon, whose lines divide the document into thirteen parts.

From Assyrian Historiography by Olmstead, A. T. (Albert Ten Eyck)