An enneagram is a nine pointed star composed of three overlapping triangles.
A nonagram is any nine-pointed polygon. In esoteric kabbalistic doctrine, it represents the sphere of Yesod, the moon, dreams and illusions. The enneagram is a well known emblem of the Baha’i faith, symbolizing the value of the word baha, “glory.”
Another type of enneagram was devised by the esoteric philosopher Gurdjieff, a nine pointed glyph. The emblem’s unusual shape is constructed by mapping the sequence of musical octaves, and has come to represent Gurdjieff’s Fourth Way Society and its philosophies.
Gurdjieff’s enneagram is likely based on the kabbalistic tree of life, and accordingly, is said to represent the underlying geometry of the universe.