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

This decades-long effort has indeed reduced emissions in America and the European Union compared with 1990 levels, the year set in the Kyoto Protocol. —Editorial, Boston Herald, 29 May 2026

The union also pointed to data that the state published shortly after adopting telework during the COVID-19 pandemic, celebrating how remote work decreased Californian’s emissions and saved state employees’ money. —William Melhado, Sacbee.com, 28 May 2026

Historically, brands have used pumice stones to achieve a worn, stonewashed look — with stones often shipped from Mexico, adding transport emissions and cost to the process. —ABC News, 28 May 2026

This process releases vast amounts of carbon dioxide, comparable to the emissions of some of the world’s largest countries. —Catarina Rolfsdotter-Jansson, Forbes.com, 28 May 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