The athame is a ceremonial knife used by a witch. It mostly has a black handle and is used to mark a magical circle example being to direct energy. Athame never used to cut anything. For the physical cutting is done by a Boline. The pointed part of the Athame blade suggests the element of fire. Indicates that it symbolises that the Athame is a balance by the chalice part that represents the water.
Nozedar Adele, The element encyclopaedia of secret signs and symbols, 2008, Athame, p 19