Avatar is derived from
ava (down) and
tṝ (to cross), describing the
descent of a deity into manifest form. "
Descent" refers to the descent of Vishnu from heaven to earth, and also to the metaphysical descent of Vishnu from his transcendent form to a material one.
Regarding the loose translation of avatāra to "incarnation", some scholars see the meaning corresponding more closely to the view of Docetism in Christian theology, as distinct from the idea of incarnation in mainstream Christology and its implication of God 'in the flesh'.
(Wikipedia)
The Avatar movie is just the latest installment from Hollywood to move us closer to accepting the New Age religious beliefs. Gnosticism, the religious belief of the Knights Templar, holds that mankind is nothing less than one of Plato's elements, Aether, trapped in a physical world and held there by Satan (they called him the demi-urge). Through multiple reincarnations, they held, a man or woman could become purified and ultimately freed from the other elements.
New Age religions call those with perfect Aether content, ascendant masters.
The Avatar, master over the elements, is really Lucifer, the angel of light. Just as the Avatar has power over the 4 elements, Lucifer has power of Satan (also known as Demi-urge). According to the New Age, he ultimately frees us from the physical elements so that we can merge with him as one collective consciousness.
Maitreya also claims the title of "Avatar." He is admittedly the servant of Lucifer inasmuch as his movement's founder, Benjamin Creme, is an admitted Luciferian.
(modified - Moneyteachers.org)