particle

n. tiny portion, very small fragment; grain; preposition; conjunction

Besides its common definition, particle may refer to: In chemistry:Colloidal particle, part of a one-phase system of two or more components In physics:Subatomic particle, which may be either:Elementary particle, a particle of which larger particles are composed, also called a fundamental particleComposite particle, a bound state between several elementary particlesPoint particle, an idealized particle that does not have any volume
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Noun
1. (nontechnical usage) a tiny piece of anything
(synonym) atom, molecule, corpuscle, mote, speck
(hypernym) material, stuff
(hyponym) grain
2. a body having finite mass and internal structure but negligible dimensions
(hypernym) body
(hyponym) virion
3. a function word that can be used in English to form phrasal verbs
(hypernym) function word, closed-class word

(n.)
The smaller hosts distributed in the communion of the laity.
  

(n.)
Any very small portion or part; the smallest portion; as, he has not a particle of patriotism or virtue.
  

(n.)
A subordinate word that is never inflected (a preposition, conjunction, interjection); or a word that can not be used except in compositions; as, ward in backward, ly in lovely.
  

(n.)
A minute part or portion of matter; a morsel; a little bit; an atom; a jot; as, a particle of sand, of wood, of dust.
  

(n.)
A crumb or little piece of concecrated host.
  

A single entity of matter (for example, proton, electron, pi meson ) or a massless energy carrier, the photon . See particle families .