One of the seven bodies of the human being. Related to Netzach, the seventh sephirah of the Tree of Life; corresponds to the fifth dimension. In Egyptian mysticism, it is called Ba. In Hinduism, is it called vijnanmayakosha or kama manas (some Hindu teachers think the mental body is "manomayakosha," but that is the astral body).
"The mental body is a material organism, yet it is not the physical organism. The mental body has its ultra-biology and its internal pathology, which is completely unknown to the present men of science." - Samael Aun Weor, The Revolution of Beelzebub.