hectotrigon or hecatontatrigon
hecatontatrigon or hectotrigon.
It works out as having 5150 diagonals
an irregular polygon
A regular polygon
an Irregular Polygon
I would just call it an "800-sided polygon."
Any polygon has 3 or more sides
A regular polygon.
The name of a sided polygon is Octaconpentagon.
Just call it a "24-sided polygon".
A cyclic polygon.