enneagon

[en-ee-uh-gon, -guhn]

noun

1. nonagon.

enneagon

/ ˈɛnɪəɡən /

noun

1. another name for nonagon

Word History and Origins

Origin of enneagon¹

1650–60; < Greek enneágōnos; ennea-, -gon

Example Sentences

And in geometry, an enneagon or nonagon is a nine-sided shape.

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