Enneagon vs. Nonagon

Enneagonnoun

(geometry) A polygon with nine sides; a nonagon.

Enneagonnoun

A polygon or plane figure with nine sides and nine angles; a nonagon.

Nonagonnoun

(geometry) a polygon with nine sides and nine angles; an enneagon

Nonagonnoun

A plane figure or polygon having nine sides and nine angles.

Nonagonnoun

a nine-sided polygon

Nonagon

In geometry, a nonagon () or enneagon () is a nine-sided polygon or 9-gon. The name nonagon is a prefix hybrid formation, from Latin (nonus, + gonon), used equivalently, attested already in the 16th century in French nonogone and in English from the 17th century.