Butterfly Theorem
Given a Chord 
of a Circle, draw any other two Chords 
and 
passing through its Midpoint. Call the points where 
and 
meet 
and 
. Then 
is the Midpoint of 
.
References
Coxeter, H. S. M. and Greitzer, S. L. Geometry Revisited. Washington, DC: Math. Assoc. Amer., pp. 45-46, 1967.
- Grassmann Manifold
- Gray Code
- Great Circle
- Great Cubicuboctahedron
- Great Deltoidal Hexecontahedron
- Great Deltoidal Icositetrahedron
- Great Dirhombicosidodecacron
- Great Dirhombicosidodecahedron
- Great Disdyakis Dodecahedron
- Great Disdyakis Triacontahedron
- Great Ditrigonal Dodecacronic Hexecontahedron
- Great Ditrigonal Dodecicosidodecahedron
- Great Ditrigonal Icosidodecahedron
- Great Dodecacronic Hexecontahedron
- Great Dodecadodecahedron
- Great Dodecahedron
- Great Dodecahedron-Small Stellated Dodecahedron Compound
- Great Dodecahemicosacron
- Great Dodecahemicosahedron
- Great Dodecahemidodecacron
- Great Dodecahemidodecahedron
- Great Dodecicosacron
- Great Dodecicosahedron
- Great Dodecicosidodecahedron
- Greater