emission

noun

emis·​sion ē-ˈmi-shən 

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 

adjective

Examples of emission in a Sentence

trying to reduce the emission of greenhouse gases

Recent Examples on the Web

Trump has also repeatedly used executive orders to deregulate fossil fuel use, such as by rolling back Biden-era limits on tailpipe emissions, and decrease immigration by, among other things, directing U.S. military troops to the southern border. —Laura Doan, CBS News, 26 Mar. 2025

Witnessing the onset of reionization through Lyman-α emission at redshift 13. —Paul Du Quenoy, MSNBC Newsweek, 26 Mar. 2025

As demand for sustainable transportation grows, startups are increasingly focusing on small electric vehicles as a solution to congestion, affordability and increasing emissions. —Akash Sriram, USA Today, 26 Mar. 2025

Friction point: Critics have raised concerns about the cruise industry's environmental impact, highlighting issues such as high carbon emissions. —Christine Clarridge, Axios, 25 Mar. 2025

Word History

First Known Use

1607, in the meaning defined at sense 1a

Phrases Containing emission

• acoustic emission
• positron-emission tomography
• re-emission
• secondary emission

Rhymes for emission

• addition
• admission
• ambition
• attrition
• audition
• clinician
• cognition
• coition
• commission
• condition
• contrition
• dentition

Kids Definition

emission

noun

emis·​sion ē-ˈmish-ən 

1

: an act or instance of emitting

2

: something emitted or discharged

emissive

ē-ˈmis-iv 

adjective

Medical Definition

emission

noun

emis·​sion ē-ˈmish-ən 

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