Henagon
From Wikipedia, the free encyclopedia
In geometry a henagon (or monogon) is a polygon with one side and one vertex. In Euclidean geometry, a henagon is usually considered to be an impossible object, because its single side would extend to infinity. However, in spherical geometry a finite henagon can be drawn by placing a single vertex anywhere on a great circle.
Since a henagon has only one side and only one interior angle, every henagon is regular by definition.