Shrichakra 

A symbolic diagram (yantra) used in worship by the Shrividya school, a particular branch of the secret ritually-based religious practice known as tantra.   

The Shrichakra is a set of nine interlocking triangles, with four pointing up, and five pointing down.  This figure is surrounded by a double series of lotus petals, then an enclosing circle, and finally angular exterior walls.  In the center of the diagram is a single point known as the bindu, which represents the ultimate divinity which is the source of all things.  

The shrichakra is considered a subtle form of the goddess Lalita Tripurasundari, a "textual" goddess who is identified with different local goddesses throughout South India.  The Shrichakra is used as a ritual aid during the rite known as samharakrama, in which the adept symbolically destroys the external world and ideas of a separate self, to become completely identified with this goddess who is considered the source of all reality.  In doing so the adept ritually "enters" the diagram through sequential rows of triangles in its sides (as illustrated in the second and third figures), eventually coming to rest in the central unifying point before reversing the symbolic journey back into the world.