par·​ti·​cle | \ ˈpär-ti-kəl How to pronounce particle (audio) \

Definition of particle

1a : a minute quantity or fragment
b : a relatively small or the smallest discrete portion or amount of something
2 archaic : a clause or article of a composition or document
3 : any of the basic units of matter and energy (such as a molecule, atom, proton, electron, or photon)
4 : a unit of speech expressing some general aspect of meaning or some connective or limiting relation and including the articles, most prepositions and conjunctions, and some interjections and adverbs the particle up has a perfective meaning in phrases such as beat up and cut up
5 : a small eucharistic wafer distributed to a Roman Catholic layman at Communion

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Examples of particle in a Sentence

There is not a particle of evidence to support their claim. There is not a particle of truth in what he said. The phrasal verb “look up” consists of the verb “look” and the adverbial particle “up.”
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Recent Examples on the Web There is no acronym and no particular name, because this particle could be many things. Rebecca Boyle, Quanta Magazine, "The Cosmologist Who Dreams in the Universe’s Dark Threads," 5 Nov. 2020 In a tweet announcing the order, the Bay Area Air Quality Management District said that cool overnight temperatures and light winds were shaping up to trap particle pollution from smoke near the ground. Ryan Kost,, "Bay Area Spare the Air alert issued for Monday due to smoke," 20 Dec. 2020 Many of the industrial sources that produce fine particle pollution, such as coal plants and vehicle tailpipes, are also large carbon emitters. Abby Smith, Washington Examiner, "EPA declines to tighten soot standards, giving industry a win before Biden," 7 Dec. 2020 One particle is sent to Charlie, the other to Debbie. Quanta Magazine, "A New Theorem Maps Out the Limits of Quantum Physics," 3 Dec. 2020 Even if an airline changed filters less often than recommended, the International Air Transport Association says air flow through the filters might be reduced but their particle-trapping capacity would not. Jen Osborne, National Geographic, "How clean is the air on planes?," 28 Aug. 2020 For instance, conventional entanglement involves linking a single characteristic (such as a particle’s spin) in multiple particles of the same type spread out in space. Clara Moskowitz, Scientific American, "Tangled Up in Spacetime," 26 Oct. 2016 Environmental Protection Agency Administrator Andrew Wheeler has decided to retain current standards for soot pollution, keeping fine-particle pollution limits adopted in 2012 that set the bar at 12 micrograms per cubic meter of air. Timothy Puko, WSJ, "EPA to Retain Existing Soot Standards After Review," 7 Dec. 2020 The agency locked in current thresholds for fine particle pollution for another five years, despite mounting evidence linking air pollution with illness and death. Author: Juliet Eilperin, Brady Dennis, Anchorage Daily News, "Trump administration rejects tougher standards on soot, a deadly air pollutant," 7 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'particle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of particle

14th century, in the meaning defined at sense 1a

History and Etymology for particle

Middle English, from Latin particula, from diminutive of part-, pars

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Time Traveler for particle

Time Traveler

The first known use of particle was in the 14th century

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Statistics for particle

Last Updated

16 Jan 2021

Cite this Entry

“Particle.” Dictionary, Merriam-Webster, Accessed 22 Jan. 2021.

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More Definitions for particle


How to pronounce particle (audio)

English Language Learners Definition of particle

: a very small piece of something
: a very small amount of something
physics : any one of the very small parts of matter (such as a molecule, atom, or electron)


par·​ti·​cle | \ ˈpär-ti-kəl How to pronounce particle (audio) \

Kids Definition of particle

: a very small bit or amount of something a particle of sand a particle of sense


par·​ti·​cle | \ ˈpärt-i-kəl How to pronounce particle (audio) \

Medical Definition of particle

1 : one of the minute subdivisions of matter (as an atom or molecule) also : elementary particle
2 : a minute quantity or fragment

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