The vesica piscis is a shape that is the intersection of two circles with the same radius, intersecting in such a way that the center of each circle lies on the perimeter of the other.
The term is also used more generally for any symmetric lens.
The vesica piscis has been the subject of mystical speculation at several periods of history.
More recently, numerous New Age authors have interpreted it as a yonic symbol and claimed that this, a reference to the female genitals, is a traditional interpretation.
One author claims that the total solar eclipse inspires images of the vesica piscis. The ancient Egyptians practiced sacred geometry based on the shape. Architects and artists copied the solar eclipse/vesica piscis and its mathematics in their sacred buildings and artwork to reflect their religious beliefs. This ancient tradition was passed on through the centuries by the Freemasons.
In Christian art, some aureolas are in the shape of a vertically oriented vesica piscis, and the seals of ecclesiastical organizations can be enclosed within a vertically oriented vesica piscis (instead of the more usual circular enclosure).
Also, the ichthys symbol incorporates the vesica piscis shape.
The cover of the Chalice Well in Glastonbury (Somerset, United Kingdom) depicts a stylized version of the vesica piscis design (see additional information).
The vesica piscis has been used as a symbol within Freemasonry, most notably in the shapes of the collars worn by officiants of the Masonic rituals. It was also considered the proper shape for the enclosure of the seals of Masonic lodges.
The vesica piscis is also used as proportioning system in architecture, in particular Gothic architecture. The system was illustrated in Cesare Cesariano’s Vitruvius (1521), which he called “the rule of the German architects”.
The Tree House 
