Definition of vapor
(Entry 1 of 2)
1
: diffused matter (such as smoke or fog) suspended floating in the air and impairing its transparency
2a
: a substance in the gaseous state as distinguished from the liquid or solid state
b
: a substance (such as gasoline, alcohol, mercury, or benzoin) vaporized for industrial, therapeutic, or military uses
also
: a mixture (such as the explosive mixture in an internal combustion engine) of such a vapor with air
3a
: something unsubstantial or transitory : phantasm
b
: a foolish or fanciful idea
4
vapors plural
a
archaic
: exhalations of bodily organs (such as the stomach) held to affect the physical or mental condition
b
: a depressed or hysterical nervous condition
vapor
verbDefinition of vapor (Entry 2 of 2)
1a
: to rise or pass off in vapor
b
: to emit vapor
2
: to indulge in bragging, blustering, or idle talk
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Merriam-Webster unabridged
Share vapor
Time Traveler for vapor
The first known use of vapor was in the 14th century
See more words from the same century