Pentagram
The Star Polygon 
, also called the Pentacle, Pentalpha, or Pentangle.
References
Ogilvy, C. S. Excursions in Geometry. New York: Dover, pp. 122-125, 1990. Pappas, T. ``The Pentagon, the Pentagram & the Golden Triangle.'' The Joy of Mathematics. San Carlos, CA: Wide World Publ./Tetra, pp. 188-189, 1989. Schwartzman, S. The Words of Mathematics: An Etymological Dictionary of Mathematical Terms Used in English. Washington, DC: Math. Assoc. Amer., 1994.
- Compact Manifold
- Compactness Theorem
- Compact Set
- Compact Space
- Compact Surface
- Companion Knot
- Comparability Graph
- Comparison Test
- Compass
- Compatible
- Complementary Angle
- Complement Graph
- Complement Knot
- Complement Set
- Complete
- Complete Axiomatic Theory
- Complete Bigraph
- Complete Bipartite Graph
- Complete Functions
- Complete Graph
- Complete k-Partite Graph
- Completely Regular Graph
- Complete Metric Space
- Completeness Property
- Complete Permutation