emission

American  

[ih-mish-uhn] / ɪˈmɪʃ ən /

noun

• emissions
  plural

1. an act or instance of emitting.

   the emission of poisonous fumes.

2. something that is emitted; discharge; emanation.

3. an act or instance of issuing, as paper money.

4. Electronics. a measure of the number of electrons emitted by the heated filament or cathode of a vacuum tube.

5. an ejection or discharge of semen or other fluid from the body.

   Synonyms:

   ejaculation

6. the fluid ejected or discharged.

   Synonyms:

   ejaculate

---

emission British  

/ ɪˈmɪʃən /

noun

1. the act of emitting or sending forth

2. energy, in the form of heat, light, radio waves, etc, emitted from a source

3. a substance, fluid, etc, that is emitted; discharge

4. a measure of the number of electrons emitted by a cathode or electron gun See also secondary emission thermionic emission

   at 1000°C the emission is 3 mA

5. physiol any bodily discharge, esp an involuntary release of semen during sleep

6. an issue, as of currency

---

Usage

What does emission mean? An emission is something that has been emitted—released or discharged. In general, emissions consist of things like gas, liquid, heat, sound, light, and radiation. Emissions can come from natural sources or from machines. A specific example of an emission is the exhaust from cars (in the U. S., such emissions are regulated through emissions tests). This exhaust is just one form of carbon emissions—greenhouse gases from various sources that are known to contribute to global warming and climate change. Emission can also refer to an instance or the process of emitting, as in This filter is designed to reduce the emission of light. Example: Carbon dioxide emissions from volcanoes are much lower than those from cars and airplanes.

Other Word Forms

Derived Forms

• nonemission
  noun
• reemission
  noun
• emissive
  adjective

Inflected Forms

Nouns

• emissions
  plural

---

Etymology

Origin of emission

First recorded in 1600–10; from Middle French or directly from Latin ēmissiōn- (stem of ēmissiō ), equivalent to ēmiss(us), past participle of ēmittere “to send forth” ( ē- “from, out of” + mit-, stem of mittere “to send” + -tus past participle suffix) + -iōn- noun suffix; see origin at emit, e- ¹, -ion

---

Explanation

An emission is something that's been released or emitted into the world. Car exhaust, burps, and radio broadcasts are all examples of emissions. Technically, an emission is anything that's been released out into the open. But more often it refers to gases being released into the air, like greenhouse gasses or emissions from power plants and factories. Anytime your body emits something (sweat, drool, gas), it's also considered an emission. Be careful not to confuse this word with the closely spelled omission — that's something that's been left out.

Example Sentences

See Examples For:

emission emissions

She said the decision would "help minimise the UK's use of imported higher emission fuels as we continue our transition to renewables and nuclear".

From BBC ● Oct. 21, 2026

Germany wanted less stringent carbon emission targets for carmakers and a broad interpretation of "made in Europe" to include key non-EU trade partners.

From Barron's ● Oct. 15, 2026

Similar signals could accompany other short GRBs but may have gone unnoticed because earlier missions were not able to capture prompt emission at energies below the gamma-ray range.

From Science Daily ● Oct. 8, 2026

Their earliest soft X-ray emission has been far more difficult to observe because most narrow-field X-ray telescopes depend on gamma-ray alerts to locate a burst before turning toward it.

From Science Daily ● Oct. 8, 2026

At this distance it would still be very difficult to detect the steady emission of a black hole, even if it was ten thousand megawatts.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

The revival of interest feels to her like a backlash against overproduction in the fashion industry and the damage it causes: the pollution, carbon emissions, water use, and poor labour conditions.

From BBC ● Oct. 30, 2026

“Our goal is to reduce port-related emissions while ensuring that the supply chain remains efficient and competitive,” Hacegaba said.

From Los Angeles Times ● Oct. 29, 2026

However, the established theory predicts a maximum energy for these emissions based on the properties of the incoming laser.

From Science Daily ● Oct. 29, 2026

Its investment objectives state it must minimise its exposure to "fossil fuel reserves and carbon emissions" where possible.

From Barron's ● Oct. 28, 2026

But it’s trees that clean carbon emissions and provide oxygen.”

From "Paradise on Fire" by Jewell Parker Rhodes

Random Word

Spin the wheel and learn a new word!

---

Related Words

• discharge
• radiation

---