ether ether /ˈiːθɝ/

noun

1. A colorless volatile highly flammable liquid formerly used as an inhalation anesthetic  ( diethyl ether , divinyl ether , ether , ethoxyethane , ethyl ether , vinyl ether )
   a colorless volatile highly flammable liquid formerly used as an inhalation anesthetic
   
   
2. A medium that was once supposed to fill all space and to support the propagation of electromagnetic waves  ( aether , ether )
   a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves
   
3. Any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom  ( ether )
   any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom
   
   
4. The fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies  ( ether , quintessence )
   the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies