noun par·ti·cle \ˈpär-ti-kəl\

Definition of particle

  1. 1a :  a minute quantity or fragmentb :  a relatively small or the smallest discrete portion or amount of something

  2. 2 archaic :  a clause or article of a composition or document

  3. 3 :  any of the basic units of matter and energy (such as a molecule, atom, proton, electron, or photon)

  4. 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. 5 :  a small eucharistic wafer distributed to a Roman Catholic layman at Communion

Examples of particle in a sentence

  1. There is not a particle of evidence to support their claim.

  2. There is not a particle of truth in what he said.

  3. The phrasal verb look up consists of the verb look and the adverbial particle up.

Origin and Etymology of particle

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

First Known Use: 14th century

PARTICLE Defined for English Language Learners


noun par·ti·cle \ˈpär-ti-kəl\

Definition of particle for English Language Learners

  • : 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)

PARTICLE Defined for Kids


noun par·ti·cle \ˈpär-ti-kəl\

Definition of particle for Students

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

Word Root of particle

The Latin word pars, meaning “part,” and its form partis give us the root part. Words from the Latin pars have something to do with a part, section, or portion. To participate is to take part in some activity. Anything partial involves only part of something. A particle is a tiny bit or portion of something. It is easy to see that part itself also comes directly from pars in both form and meaning.

Medical Dictionary


noun par·ti·cle \ˈpärt-i-kəl\

Medical Definition of particle

  1. 1:  one of the minute subdivisions of matter (as an atom or molecule); also :  elementary particle

  2. 2:  a minute quantity or fragment

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