Aethyr

Part of speech: noun

Definitions

1. A traditional name for a pure and refined upper atmosphere or ether
2. A term used in various philosophical or mystical contexts to denote a subtle element that permeates all things
3. An archaic concept representing a celestial or spiritual realm beyond the material world

Etymology: The spelling "aethyr" is simply an archaic form of "ether", and the word's oldest sense is far more concrete than its modern one. In ancient Greek, "aithēr" was the bright, pure air above the lower atmosphere, a region thought to be where the gods lived. Its root is "aithō", "to burn, ignite, blaze, shine", which is why the upper heavens were pictured as fiery and luminous rather than simply empty. Latin took the word as "aethēr", meaning the highest and purest part of the atmosphere, the sky, and even the light of day. English borrowed it through Middle French and Anglo-Norman, and in Middle English "ēther" described the substance in which the planets were thought to move, a shining fluid that was a form of air or fire. Later chemists applied the name to a volatile compound, the anaesthetic now called diethyl ether, and physicists once used it for an invisible medium believed to carry light. That second sense is now obsolete, and the spelling "aethyr" survives mainly in occult and older writing.

Synonyms: ether