Akasha

Akasha (Sanskrit ākāśa आकाश) is a term for "æther" in traditional Indian cosmology. The term has also been adopted in western occultism and spiritualism in the late 19th century.

The word in Sanskrit is derived from a root kāś meaning "to be visible". It appears as a masculine noun in Vedic Sanskrit with a generic meaning of "open space, vacuity". In Classical Sanskrit, the noun acquires the neuter gender and may express the concept of "sky; atmosphere" (Manusmrti, Shatapathabrahmana). In classical Vedantic Hindu philosophy, the word acquires its technical meaning of "an ethereal fluid imagined as pervading the cosmos". In many modern Indo-Aryan languages, the corresponding word (often rendered Akash) retains a generic meaning of "sky".

In Vedantic Hinduism, Akasha means the basis and essence of all things in the material world; the first material element created from the astral world. A Vedic mantra “pṛthivyāpastejovāyurākāśāt” indicates the sequence of initial appearance of the five basic gross elements. Thus, first appeared the space, from which appeared air, from that fire or energy, from which the water, and therefrom the earth. It is one of the Panchamahabhuta, or "five gross elements"; its main characteristic is Shabda (sound). The direct translation of Akasha is the word meaning "upper sky" or 'space' in Hinduism.

The Nyaya and Vaisheshika schools of Hindu philosophy state that Akasha or aether is the fifth physical substance, which is the substratum of the quality of sound. It is the One, Eternal, and All Pervading physical substance, which is imperceptible.

According to the Samkhya school of Hindu philosophy, Akasha is one of the five Mahābhūtas (grand physical elements) having the specific property of sound.

...
Wikipedia