va·​por | \ ˈvā-pər How to pronounce vapor (audio) \

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


vapored; vaporing\ ˈvā-​p(ə-​)riŋ How to pronounce vaporing (audio) \

Definition of vapor (Entry 2 of 2)

intransitive verb

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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Other Words from vapor


vaporer \ -​pər-​ər How to pronounce vaporer (audio) \ noun

Synonyms for vapor

Synonyms: Verb

blow, boast, brag, bull [slang], crow, gasconade, swagger, vaunt

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Did You Know?


Speakers of the English language, mindful of the lightness and unsubstantiality of floating air and gas, have put several airy words to good use over the years to describe the act of talking idly or boastfully. The earliest such word is blow (as in "he kept blowing about his new job"), which drifted into English sometime about 1400. Vapor wafted into the language in the 1620s, and a little over 200 years later windbags, later also known as gasbags, not only blew and vapored but also gassed about anything they could.

Examples of vapor in a Sentence


a faded Southern belle tiresomely vaporing about all the handsome beaux she had in her long-ago youth

Recent Examples on the Web: Noun

Tanklike devices called solar stills use the sun to evaporate dirty or salty water and condense the vapor into safe drinking water. Robert F. Service, Science | AAAS, "New solar technology could produce clean drinking water for millions in need," 28 June 2019 The purified vapor condenses into water, which flows into a tank that also serves as a footrest. Manuel Canales, National Geographic, "These new toilets could solve a global problem," 22 June 2019 The leak produced a large vapor cloud in the air, and a Houston Fire Department hazmat crew was checking the air quality in the area overnight. Julian Gill, Houston Chronicle, "Chemical leak reported at a manufacturing facility in NW Houston," 18 June 2019 Superior Mayor Jim Paine and Duluth Mayor Emily Larson have asked the company to find a safer alternative to hydrogen fluoride, which can produce toxic vapor clouds. Dino Grandoni, Washington Post, "The Energy 202: Interior agency blocks group of archaeologists from attending scientific conference," 3 May 2018 The vapor cloud is so small and dissipates so quickly that teachers are usually none the wiser, said Luna, who added he's never tried it himself. Ana B. Ibarra, CNN, "Juul e-cigarettes and teens: 'Health problem of the decade'?," 15 Mar. 2018 While the workers were spray painting the interior, the flammable vapors built up and then were ignited, causing a flash fire which quickly engulfed the home. Jeff Forward, Houston Chronicle, "Fire Marshal: Spray paint fumes ignited, causing mansion fire in The Woodlands," 18 June 2019 The warm vapor makes contact with cooled stainless steel coils inside, and, similar to that inconvenient water that drips from your air conditioning unit, condensation is created. Andrew Boryga,, "Just add humidity: How this air-to-water machine can quench your thirst," 17 June 2019 As the oxygen was pumped in, some of it boiled off; vents at the top of the tank let the vapor out so that pressure within would not get too high. Oliver Morton, WIRED, "The Beauty and Madness of Sending a Man to the Moon," 4 June 2019

Recent Examples on the Web: Verb

But whole body cryotherapy exposes the body for a couple of minutes to vapor that has been supercooled to somewhere between minus 200 and minus 300 degrees Fahrenheit. Aaron E. Carroll, New York Times, "Cold Therapy? Maybe Better Save Your Money," 2 Jan. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'vapor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of vapor


14th century, in the meaning defined at sense 1


15th century, in the meaning defined at sense 1a

History and Etymology for vapor


Middle English vapour, borrowed from Anglo-French & Latin; Anglo-French vapor, vapour, borrowed from Latin vapor, earlier vapōs "exhalation, steam, warmth," perhaps akin to Lithuanian kvãpas "smell, scent"

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Statistics for vapor

Last Updated

12 Jul 2019

Look-up Popularity

Time Traveler for vapor

The first known use of vapor was in the 14th century

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More Definitions for vapor



English Language Learners Definition of vapor

: a substance that is in the form of a gas or that consists of very small drops or particles mixed with the air


va·​por | \ ˈvā-pər How to pronounce vapor (audio) \

Kids Definition of vapor

1 : fine bits (as of fog or smoke) floating in the air and clouding it
2 : a substance in the form of a gas water vapor


variants: or chiefly British vapour \ ˈvā-​pər How to pronounce vapour (audio) \

Medical Definition of vapor

1a : a substance in the gaseous state as distinguished from the liquid or solid state
b : a substance (as alcohol or benzoin) vaporized for industrial, therapeutic, or military uses

2 vapors or chiefly British vapours plural

a : exhalations of bodily organs (as the stomach) formerly held to affect the physical or mental condition
b : a depressed or hysterical nervous condition

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More from Merriam-Webster on vapor

Rhyming Dictionary: Words that rhyme with vapor

Thesaurus: All synonyms and antonyms for vapor

Spanish Central: Translation of vapor

Nglish: Translation of vapor for Spanish Speakers

Britannica English: Translation of vapor for Arabic Speakers

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food or victuals

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