A very small piece of matter, a fragment; especially, the smallest possible part of something.

plural of particle

(physics) An energetic electron or positron produced as the result of a nuclear reaction or nuclear decay.

Any of many units of matter smaller than an atom.

(US, Canada) a structural material manufactured from wood particles (such as chips and shavings) by pressing, and binding through resin

(informal) The Higgs boson.

(physics) A positively charged nucleus of a helium-4 atom (consisting of two protons and two neutrons), emitted as a consequence of radioactivity; α-particle

(nuclear physics) A subatomic particle that is not an elementary particle, i.e. a hadron or an atomic nucleus.

beta particle

(physics) A fundamental particle; any of the subatomic particles that do not consist of other, smaller particles; the gauge bosons, leptons and quarks.