decagon

noun

deca·gon ˈde-kə-ˌgän

: a plane polygon of 10 angles and 10 sides

Word History

Etymology

New Latin decagonum, from Greek dekagōnon, from deka- deca- + -gōnon -gon

First Known Use

circa 1639, in the meaning defined above

Time Traveler

The first known use of decagon was circa 1639

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decaffeinize

decagon

decagram

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Cite this Entry

Style

“Decagon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decagon. Accessed 19 Jun. 2025.

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Kids Definition

decagon

noun

deca·gon ˈdek-ə-ˌgän

: a polygon of 10 angles and 10 sides

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