Ethereal (ĭ-thîr'ē-əl) characterized by lightness and insubstantiality; as impalpable or intangible as air.

 "Figures light and aeriform come unlooked for and melt away" -Thomas Carlyle

Anima mundi (Latin) is the world soul, a pure ethereal spirit diffused throughout all nature.
It animates all matter in the same sense in which the soul animates the human.

“Therefore, we may consequently state that:
this world is indeed a living being endowed with a soul and intelligence ...
a single visible living entity containing all other living entities,
 which by their nature are all related.”

—Plato, Timaeus, 29/30; 4th century BCE