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.
This El Niño weather pattern is on top of warming temperatures that result from fossil fuel emissions, which trap more heat in the atmosphere. — Ava Berger, NPR, 29 Oct. 2026 Many African policymakers responded that advanced economies built their wealth on coal and oil, adding that Africa accounts for less than 4% of global carbon emissions. — Alexis Akwagyiram, semafor.com, 28 Oct. 2026 The next governor will decide whether to continue Newsom’s ambitious plan to accelerate the transition to zero-emission vehicles by banning the sale of new gas cars in California by 2035. — Seema Mehta, Los Angeles Times, 28 Oct. 2026 Researchers were able to see what chemicals were in the smoke, track how its composition changed over the fire's course, and distinguish emissions coming from burning structures. — ABC News, 28 Oct. 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 29 Oct. 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

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