emis·sion | \ ē-ˈmi-shən \

Definition of emission 

1a : an act or instance of emitting : emanation

b archaic : publication

c : a putting into circulation

2a : 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

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Other words from emission

emissive \ē-ˈmi-siv \ adjective

Examples of emission in a Sentence

trying to reduce the emission of greenhouse gases

Recent Examples on the Web

Greenhouse gas emissions vary considerably across the region, the plan stated. Susan Demar Lafferty, Daily Southtown, "CMAP plan draws variety of comments," 14 July 2018 The alliance pledged to help engineer the distribution of 100 million cookstoves, small-scale appliances designed to cut fuel use and toxic emissions in impoverished households worldwide by 2020. Sara Morrison, USA TODAY, "In developing world, an expensive push to reduce cooking fire deaths falls short," 13 July 2018 The study suggested that increased methane emissions — added to the atmosphere by humans extracting and burning fossil fuels — have increased water vapor concentrations in the mesosphere by about 40 percent since the late 1800s. Katie Camero, BostonGlobe.com, "Once-rare cloud is now more common, and new study says climate change is to blame," 13 July 2018 The state’s next target is to drop emissions by another 40 percent by 2030. Dino Grandoni, Washington Post, "The Energy 202: Republicans can't agree on this climate deal brokered by Obama," 12 July 2018 People wind up burning the plastic trash and inhaling toxic emissions, according to the United Nations. Emily Atkin, The New Republic, "Critics of Starbucks’ Straw Ban Are Missing the Point," 12 July 2018 Government restrictions on carbon emissions have spawned a large renewable-energy industry specializing in solar panels and windmills. George Melloan, WSJ, "Pruitt Leaves a Proud Legacy at the EPA," 11 July 2018 Maricopa County air-quality officials say their hands are tied because the plant's emissions are within its permit guidelines. Lily Altavena, azcentral, "Controversy in the air as Mesa homeowners decry neighboring asphalt plant’s odors," 11 July 2018 The carbon emission implications of teardowns is significant, and taking the renovation instead of removal route can have significantly better results. Patrick Sisson, Curbed, "How teardowns hurt housing affordability, and how to fix it," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'emission.' 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 emission

1607, in the meaning defined at sense 1a

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Statistics for emission

Last Updated

9 Sep 2018

Look-up Popularity

Time Traveler for emission

The first known use of emission was in 1607

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More Definitions for emission



English Language Learners Definition of emission

: the act of producing or sending out something (such as energy or gas) from a source

: something sent out or given off


emis·sion | \ ē-ˈmi-shən \

Kids Definition of emission

1 : the act of giving off The energy plant is reducing the emission of harmful gases.

2 : something that is given off Scientists can record radio emissions from far-off stars.


emis·sion | \ ē-ˈmish-ən \

Medical Definition of emission 

1 : an act or instance of emitting

2a : 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

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More from Merriam-Webster on emission

Spanish Central: Translation of emission

Nglish: Translation of emission for Spanish Speakers

Britannica English: Translation of emission for Arabic Speakers

Britannica.com: Encyclopedia article about emission

Comments on emission

What made you want to look up emission? Please tell us where you read or heard it (including the quote, if possible).


occurring twice a year or every two years

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