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

Ship operators and bunker providers are wrestling with preparations for looming sulfur-emissions restrictions while fuel prices have soared over the past year as the cost of crude has increased. Paul Page, WSJ, "Today’s Logistics Report: Labor Peace in Trucking; Tankers in Rebound; Supplier Tariff Tensions," 12 Nov. 2018 Now, the company has teamed up with Toyota to build the Tundra PIE Pro, a zero-emission pickup with a robotic pizza-making factory in the truck bed. Dami Lee, The Verge, "The Tundra PIE Pro is a pickup truck that makes Pizza Hut on the go," 30 Oct. 2018 It single-handedly accounts for about 7 percent of all global carbon emissions, according to estimates from the International Energy Agency. Chelsea Harvey, Scientific American, "Cement Producers Are Developing a Plan to Reduce CO2 Emissions," 9 July 2018 Uber’s program aligns with an executive order issued by Gov. Jerry Brown this year that calls on California, home to 410,000 EVs, to increase the number of zero-emission vehicles to five million by 2030. Tracey Lien And Jennifer Van Grove, Philly.com, "Uber begins a push to get its drivers into electric cars," 28 June 2018 But some scientists say no amount of rebound will prevent ice sheet collapse in the long term, given the pace of carbon emissions and global warming. Katie Langin, Science | AAAS, "Rising bedrock below West Antarctica could delay catastrophic ice sheet collapse," 21 June 2018 On one front, the Environmental Protection Agency is fighting to roll back auto-emissions standards that had been put into place by the Obama administration. Jonathan Chait, Daily Intelligencer, "Trump’s Environmental Agenda No Longer Pretending to Care About the Free Market," 14 May 2018 The measure establishes a community-wide goal of transitioning to 100 percent renewable energy by 2050, and also says the city’s fleet vehicles will be zero-emission by 2035. Joshua Sharpe, ajc, "DeKalb city run by millennials is switching to 100% clean energy," 3 May 2018 Likewise, French officials have suggested that Macron is less anxious about trying to persuade Trump to back the global climate deal, which commits each country to carbon-emissions targets in order to dramatically rein in global warming. Time, "Emmanuel Macron Takes a Risky Bet with Visit to U.S. to Charm Donald Trump," 22 Apr. 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

18 Nov 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

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by force of circumstances

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