Definition:Number Prefixes/9/Ennea-

Definition

The prefix ennea- denotes $9$.

Examples

The prefix ennea- can be found in the following contexts:

• ennead: a set or ordered tuple with $9$ elements

• enneagon: a polygon with $9$ sides and hence $9$ vertices

• enneahedron: a polyhedron with $9$ faces

Linguistic Note

The prefix ennea- is from the Classical Greek ἐννέα (ennéa), meaning nine.

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): ennea- or nona-