emission

noun

emis·​sion ē-ˈmi-shən How to pronounce emission (audio)
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
emissive 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.
Recent renovations have prioritized natural materials, while cutting-edge heat pump systems now provide emission-free heating and cooling throughout the hotel. Susmita Baral, Travel + Leisure, 7 Sep. 2025 How much producers want to reduce carbon emissions and waste depends in part on production budgets — but also on learning best practices. Etan Vlessing, HollywoodReporter, 7 Sep. 2025 This mechanism explains why PAH emission is detectable at such vast distances from the galaxy, according to the statement. Sharmila Kuthunur, Space.com, 7 Sep. 2025 Keep in mind that every carmaker in the Seventies struggled to adapt to emissions regulations and still produce engines with any amount of power. Mark Ewing, Forbes.com, 7 Sep. 2025 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

Browse Nearby Words

Cite this Entry

“Emission.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/emission. Accessed 10 Sep. 2025.

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 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
Last Updated: - Updated example sentences
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