Great Rite is a powerful, magickal rite of sexual intercourse, in both Wiccan and neo-Paganism groups.  It symbolizes the physical, mental, spiritual and astral union between man and woman as they, in turn, represent the God and Goddess aspects of Divinity.  This is also observed in the yab-yang images found in Eastern religions.

The Great Rite is associated with the hieros gamos, the Sacred Marriage or Holy Matrimony, in which a mortal is united with the deity or godhead. The hieros gamos was part of pre-Christian women's mysteries in Mesopotamia and the Mediterranean, in which women sacrificed control of their feminine power to the Goddess to be renewed by her. A remnant of this is found n the Roman Catholic Church, in which nuns are united in marriage to Christ.

It is believed that  the Great Rite releases enormous power, which may be directed for magical purposes. 

The Great Rite is performed in the Circle at some Sabbats and initiations, depending on the tradition of the coven. Ideally, it is performed by a High Priest and High Priestess who are already sexually intimate, except in the rite of handfasting, where the bride and groom, who may not  already be intimate lovers, perform the rite. Today, the rite is seldom performed in actuality, but may be performed symbolically; when the High Priest plunges the athame, or ritual knife (the lingam), into a cup or chalice (the yonil) that is filled with wine and is held by the High Priestess. In some covens, after this rite is performed symbolically it is later performed in actuality by the High Priest and High Priestess. In this case the  coven members leave the circle (Though in some covens, they merely walk to the edge of the Circle and turn their backs.   When the Rite is consumated between the High Priest and High Priestess,, they will ring a bell to call the coven members back to the circle.