emission

noun

emis·​sion ē-ˈmi-shən How to pronounce emission (audio)
Synonyms of emissionnext
1
a
: an act or instance of emitting : emanation
b
archaic : publication
c
: a putting into circulation
2
a
: something sent forth by emitting: such as
(1)
: electromagnetic radiation from an antenna or a celestial body
(2)
usually emissions : substances discharged into the air (as by a smokestack or an automobile engine)
b
: effluvium
emissive
ē-ˈmi-siv How to pronounce emission (audio)
adjective

Examples of emission in a Sentence

trying to reduce the emission of greenhouse gases
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Waste plastic could provide another source of hydrocarbons for fuel production, particularly as governments and industry look for ways to deal with both plastic waste and aviation emissions. — Bojan Stojkovski, Interesting Engineering, 30 Aug. 2026 The study defined high-exposure counties as having median annual emissions of 51 pounds of ethylbenzene and 44 pounds of toulene. — Clara Harter, Los Angeles Times, 30 Aug. 2026 Planet-heating emissions from burning fossil fuels such as oil, gas and coal are the primary driver of climate change. — Ava Berger, NPR, 28 Aug. 2026 Among the various green commitments and innovations of note, all of Explora’s ships are RINA Dolphin-certified for their low-level of underwater noise emissions, which helps preserve marine life. — Condé Nast, Condé Nast Traveler, 28 Aug. 2026 See All Example Sentences for emission

Word History

First Known Use

1607, in the meaning defined at sense 1a

Time Traveler
The first known use of emission was in 1607

Phrases Containing emission

Rhymes for emission

See All Rhymes for emission

Browse Nearby Words

emissile
emission
emission line
See all Nearby Words

Cite this Entry

“Emission.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/emission. Accessed 1 Sep. 2026.

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Kids Definition

emission

noun
emis·​sion ē-ˈmish-ən How to pronounce emission (audio)
1
: an act or instance of emitting
2
: something emitted or discharged
emissive
ē-ˈmis-iv How to pronounce emission (audio)
adjective

Medical Definition

emission

noun
emis·​sion ē-ˈmish-ən How to pronounce emission (audio)
1
: an act or instance of emitting
2
a
: something sent forth by emitting: as
(1)
: electrons discharged from a surface
(2)
: electromagnetic waves radiated by an antenna or a celestial body
(3)
: substances and especially pollutants discharged into the air (as by a smokestack or an automobile gasoline engine)
b
: a discharge of fluid from a living body
especially : ejaculate see nocturnal emission

More from Merriam-Webster on emission

Thesaurus: All synonyms and antonyms for emission

Britannica.com: Encyclopedia article about emission

Last Updated: - Updated example sentences
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