particle

American  

[pahr-ti-kuhl] / ˈpɑr tɪ kəl /

noun

1. a minute portion, piece, fragment, or amount; a tiny or very small bit.

   a particle of dust; not a particle of supporting evidence.

   Synonyms:

   speck, grain, tittle, jot, iota, whit, mite

2. Physics.

   1. one of the extremely small constituents of matter, as an atom or nucleus.

   2. an elementary particle, quark, or gluon.

   3. a body in which the internal motion is negligible.

3. a clause or article, as of a document.

4. Grammar.

   1. (in some languages) one of the major form classes, or parts of speech, consisting of words that are neither nouns nor verbs, or of all uninflected words, or the like.

   2. such a word.

   3. a small word of functional or relational use, as an article, preposition, or conjunction, whether of a separate form class or not.

5. Roman Catholic Church. a small piece of the Host given to each lay communicant in a Eucharistic service.

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particle British  

/ ˈpɑːtɪkəl /

noun

1. an extremely small piece of matter; speck

2. a very tiny amount; iota

   it doesn't make a particle of difference

3. a function word, esp (in certain languages) a word belonging to an uninflected class having suprasegmental or grammatical function

   the Greek particles ``mēn'' and ``de'' are used to express contrast

   questions in Japanese are indicated by the particle ``ka''

   English ``up'' is sometimes regarded as an adverbial particle

4. a common affix, such as re-, un-, or -ness

5. physics a body with finite mass that can be treated as having negligible size, and internal structure

6. See elementary particle

7. RC Church a small piece broken off from the Host at Mass

8. archaic a section or clause of a document

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particle Scientific  

/ pär′tĭ-kəl /

1. A very small piece of solid matter.

2. An elementary particle, subatomic particle, or atomic nucleus.

3. Also called corpuscle

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Other Word Forms

• interparticle
  adjective
• particled
  adjective

Etymology

Origin of particle

First recorded in 1350–1400; Middle English word from Latin word particula. See part, -i-, -cle ¹

Explanation

A particle is a small piece of anything. Particle can also refer to a subatomic particle with mass and structure, but takes up hardly any space at all. Particles are tiny. If you mean a subatomic particle, that's a body that you can't see because it is so incredibly small, though it does have a miniscule mass and internal structure. These particles are even smaller than atoms. You can also say a crumb or speck of something is a particle. Dust particles are piling up all the time, and vacuuming cleans up lots of particles. Those particles are little bits of things. In both cases, particles are very tiny.

Example Sentences

Because of this extreme complexity, accurately predicting the muon's behavior within the Standard Model has remained one of the most difficult problems in particle physics.

From Science Daily • May 19, 2026

Testing string theory directly would require energies so extreme that researchers would need a particle collider as large as a galaxy.

From Science Daily • May 19, 2026

Scientists say the new results place tighter limits on existing models of particle acceleration in astrophysical sources and improve our understanding of how high-energy particles move through interstellar space.

From Science Daily • May 14, 2026

Correction 20 March: This piece was updated to remove a claim that the entire proposed cut of £162m was to research into particle physics and astronomy.

From BBC • Mar. 18, 2026

This is still not nearly powerful enough to see strings or curled-up dimensions—viewing strings would require a particle accelerator about 6,000,000,000,000,000 miles around.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Related Words

• fleck
• fragment
• grain
• mite
• molecule
• ray
• speck