English Reference
noun

particle

n.
US /ˈpɑɹtəkəɫ/ UK /pˈɑːtɪkəl/ par·ti·cle UK spelling particle's, particle's

  1. 01 B2 Upper Intermediate

    a very small piece of something, such as dust, dirt, or sand.

    a minute fragment or quantity of matter.

    Simple

    A tiny particle of dust got into my eye and made it water.

    In context

    The air filtration system was designed to capture even the smallest particles of soot produced by the nearby factory.

  2. 02 C1 Advanced Technical Science

    one of the tiny parts that make up an atom, like an electron.

    any of the subatomic constituents of matter or energy, such as protons, neutrons, or photons.

    Simple

    Scientists use huge machines to study how particles move and crash into each other.

    In context

    The experiment aimed to observe the decay of the Higgs boson, a fundamental particle that explains why other particles have mass.

    subatomic particle
  3. 03 C1 Advanced Technical Science

    a small word that does not change its form and helps other words, like 'to' in 'to go' or 'up' in 'look up'.

    a function word that does not belong to a major inflected grammatical class and lacks a distinct lexical meaning of its own.

    Simple

    In the phrasal verb 'give up', the word 'up' is a particle.

    In context

    The teacher explained that the infinitive particle 'to' is grammatically distinct from the preposition 'to' used for direction.

    Usage

    In English, this term often refers to the 'to' in infinitives or the adverbial elements of phrasal verbs.

    function word
  4. 04 C2 Proficiency LiteraryFormal

    a very small amount of a quality or feeling.

    the smallest possible amount or trace of an abstract quality.

    Simple

    There was not a particle of truth in the rumors about the scandal.

    In context

    He spoke with such absolute conviction that not a single particle of doubt remained in the minds of the jury.

Usage particle physics · particles interact

What is heat, and what is useful work if a machine consists only of an atom and light particles?

Phys.org· 17 Aug 2026

He added that the UK was and would continue to be the second biggest funder of particle physics experiments at CERN.

BBC News· 18 Mar 2026

From Middle French particule, and its source, Latin particula (“small part, particle”), diminutive of pars (“part, piece”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated