Nonagon
/ˈnɒn.ə.ɡɒn/noun
A polygon with nine sides and nine angles.
Did you know?The -gon in nonagon comes from the same Greek root behind “protagonist” and “polygon,” all ultimately tied to the idea of an angle or corner.
Etymological Timeline
Ancient Greek
Greek
ennea gōnon
“nine-angled”
Late Latin
Latin
nonagonum
“a nine-sided figure”
14th–16th Century
French/Latin
nonagone
“a nine-sided polygon”
16th Century
English
nonagon
“a nine-sided polygon”
Modern English
English
nonagon
“a polygon with nine sides and nine angles”
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