the purest and most concentrated essence of something | a colorless volatile highly flammable liquid formerly used as an inhalation anesthetic |
the most typical example or representative of a type | a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves |
the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies | any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom |
| the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies |