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

The researchers say that if the emission cone could be narrowed sufficiently to better match the absorption cone of sunlight, efficiencies approaching 43 percent could theoretically become possible. — Kaif Shaikh, Interesting Engineering, 7 Oct. 2026

Consider a textile mill considering an investment in new equipment which will lower their carbon emission along with other environmental benefits. — Lewis Perkins, Footwear News, 7 Oct. 2026

Boulder is not trying to regulate greenhouse gas emissions or stop the companies from continuing to produce oil and gas, Russell said. — Arkansas Online, 6 Oct. 2026

Google’s carbon emissions rose by 18 percent last year along with a jump in electricity demand of 37 percent, according to the company’s latest sustainability report. — Justine Calma, The Verge, 6 Oct. 2026

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