Incarnation of God or a god in human or other modosophont form.
In Brahmanic-based religion, an embodiment or a bodily manifestation of the divine, from the Sanskrit Avatara which means "descent", i.e. the descent of the divine into human form. Original Hindu mythology was full of stories of avatars (Rama and Krishna were the two most popular) and their various exploits and past-times.
Interplanetary age religions like the Universal Church, Wider Christianity, and New Bahaism - often based on integrating Indian insights with Semitic religions - referred to classical or industrial age prophetic founders like Christ or Baha'ullah (and later, Mohammad in some heterodox and Sufi-based forms of the Stellar Umma) as "avatars of God". Many Nuage and neo-nuage sects and cults each had their own (usually baseline, more rarely su) human avatar (often shown by objective analysis to be an exploitative fraud). Also, genuine religious founders throughout history frequently found themselves considered avatars by their followers, but they generally did not encourage such claims.
Since the Empires Age the term has been used to designate the representative of a high transapient or archai in anthropomorphic form - e.g. the Godtech Avatar, Baphomet, and the Green and Blue Goddess. See Avatar (Archai).