deca·​gon ˈde-kə-ˌgän How to pronounce decagon (audio)
: a plane polygon of 10 angles and 10 sides

Illustration of decagon

Illustration of decagon

Word History


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

Dictionary Entries Near decagon

Cite this Entry

“Decagon.” Dictionary, Merriam-Webster, Accessed 20 May. 2024.

Kids Definition


deca·​gon ˈdek-ə-ˌgän How to pronounce decagon (audio)
: a polygon of 10 angles and 10 sides
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