Particle (grammar)

In grammar the term particle (abbreviated PTCL) has a traditional meaning, as a part of speech that cannot be inflected, and a modern meaning, as a function word associated with another word or phrase to impart meaning.

In modern grammar, a particle is a function word that must be associated with another word or phrase to impart meaning, i.e., does not have its own lexical definition. On this definition, particles are a separate part of speech and are distinct from other classes of function words, such as articles, prepositions, conjunctions and adverbs. Languages vary widely in how much they use particles, some using them extensively and others more commonly using alternative devices such as prefixes/suffixes, inflection, auxiliary verbs and word order. Particles are typically words that encode grammatical categories (such as negation, mood, tense, or case), clitics, or fillers or (oral) discourse markers such as well, um, etc. Particles are never inflected.

Depending on context, the meaning of the term may overlap with concepts such as morpheme, marker, or even adverb as in English phrasal verbs such as out in get out. Under a strict definition, in which a particle must be uninflected, English deictics like this and that would not be classed as such (since they have plurals and are therefore inflected), and neither would Romance articles (since they are inflected for number and gender).

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