Grammatical particle
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 (functor) associated with another word or phrase in order to impart meaning. Although a particle may have an intrinsic meaning and may fit into other grammatical categories, the fundamental idea of the particle is to add context to the sentence, expressing a mood or indicating a specific action.