[ ih-mish-uhn ]
See synonyms for: emissionemissions on Thesaurus.com

  1. an act or instance of emitting: the emission of poisonous fumes.

  2. something that is emitted; discharge; emanation.

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

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

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

  4. the fluid ejected or discharged.

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

Other words for emission

Other words from emission

  • non·e·mis·sion, noun
  • re·e·mis·sion, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use emission in a sentence

British Dictionary definitions for emission


/ (ɪˈmɪʃən) /

  1. the act of emitting or sending forth

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

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

  2. a measure of the number of electrons emitted by a cathode or electron gun: at 1000°C the emission is 3 mA See also secondary emission, thermionic emission

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

  4. an issue, as of currency

Origin of emission

C17: from Latin ēmissiō, from ēmittere to send forth, emit

Derived forms of emission

  • emissive, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012