- gonOne hundredth of a right angle: a gradian.
- -gonForms the names of plane figures containing a given number of internal angles, and thus bounded by that number of line segments (polygons).
- gonio-angle.
- goniorhynchidAny of the extinct microsaur genus †Goniorhynchus (a synonym of †Rhynchonkos).
- hexacontagonA 60-sided polygon.
- OrthogonianA member of the Orthogonian society, a social club at Whittier College founded by Richard M. Nixon in opposition to the wealthy elites at Whittier.