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noun phe·nom·e·non \fi-ˈnä-mə-ˌnän, -nən\

Simple Definition of phenomenon

  • : something (such as an interesting fact or event) that can be observed and studied and that typically is unusual or difficult to understand or explain fully

  • : someone or something that is very impressive or popular especially because of an unusual ability or quality

Source: Merriam-Webster's Learner's Dictionary

Full Definition of phenomenon



play play \-nə, -ˌnä\ or


  1. 1 plural phenomena :  an observable fact or event

  2. 2 plural phenomena a :  an object or aspect known through the senses rather than by thought or intuition b :  a temporal or spatiotemporal object of sensory experience as distinguished from a noumenon c :  a fact or event of scientific interest susceptible to scientific description and explanation

  3. 3 a :  a rare or significant fact or event b plural phenomenons :  an exceptional, unusual, or abnormal person, thing, or occurrence

Usage Discussion of phenomenon

Phenomena has been in occasional use as a singular for more than 400 years and its plural phenomenas for more than 350. Our evidence shows that it is primarily a speech form used by poets, critics, and professors, among others, but one that sometimes turns up in edited prose <the Borgia were, in modern terms, a media phenomenaEconomist>. It is etymologically no more irregular than stamina, agenda, and candelabra, but it has nowhere near the frequency of use that they have, and while they are standard, phenomena is still rather borderline.

Examples of phenomenon in a sentence

  1. For example, we talk more loudly in cars, because of a phenomenon known as the Lombard effect—the speaker involuntarily raises his voice to compensate for background noise. —John Seabrook, New Yorker, 23 June 2008

  2. This follow-the-winemaker phenomenon is a unique wrinkle in our wine culture. —James Laube, Wine Spectator, 15 May 2008

  3. Contrary to the notion that war is a continuation of policy by other means … , both Keegan and Mueller find that war is a cultural product rather than a phenomenon or law of nature and therefore subject, like other modes of human expression (the wearing of togas or powdered wigs, the keeping of slaves, the art of cave painting), to the falling out of fashion. —Lewis H. Lapham, Harper's, September 2007

  4. The days and nights of the Irish pub, smoky and dark and intimate, are giving way to another phenomenon: the superpub. These are immense places, loud with music; part honkytonk, part dance hall, some servicing as many as a thousand drinkers on several floors. —Pete Hamill, Gourmet, April 2007

  5. They were ephemera and phenomena on the face of a contemporary scene. That is, there was really no place for them in the culture, in the economy, yet they were there, at that time, and everyone knew that they wouldn't last very long, which they didn't. —William Faulkner, letter, 7 Mar. 1957

  6. natural phenomena like lightning and earthquakes

  7. the greatest literary phenomenon of the decade

  8. The movie eventually became a cultural phenomenon.

Origin and Etymology of phenomenon

Late Latin phaenomenon, from Greek phainomenon, from neuter of phainomenos, present participle of phainesthai to appear, middle voice of phainein to show — more at fancy

First Known Use: 1605

PHENOMENON Defined for Kids


noun phe·nom·e·non \fi-ˈnä-mə-ˌnän\

Definition of phenomenon for Students



\-nə\ or


  1. 1 plural phenomena :  an observable fact or event

  2. 2 :  a rare or important fact or event

  3. 3 plural phenomenons :  an extraordinary or exceptional person or thing

Medical Dictionary


noun phe·nom·e·non \fi-ˈnäm-ə-ˌnän, -nən\

Medical Definition of phenomenon



\-nə, -ˌnä\play
  1. 1:  an observable fact or event

  2. 2a:  an object or aspect known through the senses rather than by thought or intuitionb:  a fact or event of scientific interest susceptible of scientific description and explanation

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