SynonymDefinitionAntonym.com - English Synonym Dictionary

A colorless volatile highly flammable liquid formerly used as an inhalation anesthetic

A medium that was once supposed to fill all space and to support the propagation of electromagnetic waves

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