1. [ noun ] a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves
Synonyms: aether
Related terms: medium
2. [ noun ] (archaic) the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies
Synonyms: quintessence
Related terms: element archaism
3. [ noun ] (chemistry) any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom
Related terms: organic_compound
4. [ noun ] (chemistry,medicine,pharmacology,surgery) a colorless volatile highly inflammable liquid used as an inhalation anesthetic
Synonyms: divinyl_ether vinyl_ether diethel_ether ethyl_ether diethyl_ether ethoxyethane
Related terms: inhalation_anesthetic enflurane etherize
Similar spelling:   Etter