November
The word is, surprisingly, "nonagon".
nonagon is one good word
Ennead, enneadic, ninth, nonagon, novenary...
Because nonagon means 9 sides
Nonagon is the appropriate word for a nine sided plane figure
A nonahedron, which is a 3D shape with 9 faces.
First you must determin what the "apothem" is, and by that i mean what the hell that word means.
The most common term is "nonagon", though technically "non-" is a Latin prefix. The purely Greek word for it is "enneagon." But no one really uses this term , so you're safe with "nonagon."
A nonagon is a polygon with nine sides. The prefix "nona-" in nonagon comes from the Latin word for "nine." Each side of a nonagon connects to two other sides, forming a total of nine straight sides that enclose the shape.
Nonagonal.
nonaligned?
A nonagon has nine vertices. It is a polygon with nine sides, and each vertex corresponds to one of these sides. The term "nonagon" comes from the Latin word "nonus," meaning nine.