Ether


 * Ether (chemistry): A functional group in organic chemistry, often used as a part anesthetic and often very volatile and flammible.
 * Luminiferous aether: Also known as the aether or ether.  Originally theorised as the material that composed the universe.  The existence of the luminiferous aether was disproved by the Michelson-Morley experiment in 1887.
 * Ether (classical element): Originating with Aristotle, aether was "quintessence" or "essence" and was a pure, fifth heavenly element which the gods breathed.
 * Aether (mythology):  The personification (i.e., an "elemental god") of the upper sky, space and heaven.  The aether of 19th century physics and the classical element is named after this god.
 * Ethereum, a type of cryptocurrency
 * Ethernet, a medium-access protocol sublayer named after the luminiferous aether.