enneagonal
/ɛnɪˈæɡənəl/Definitions
1. adjective
Having nine angles.
“The mathematician studied the enneagonal shape in her research on polyhedra.”
2. noun
A polygon with nine angles.
“The artist used an enneagonal shape as the centerpiece of her sculpture.”
3. noun
A polyhedron with nine faces.
“The engineer designed a complex enneagonal structure for the new skyscraper.”