particle vs closed-class word

particle and closed-class word both are nouns.

Word	Noun	Adjective	Verb	Adverb
particle	Yes	No	No	No
closed-class word	Yes	No	No	No

As nouns, closed-class word is a hypernym of particle; that is, closed-class word is a word with a broader meaning than particle:

particle: a function word that can be used in English to form phrasal verbs
closed-class word: a word that is uninflected and serves a grammatical function but has little identifiable meaning

Other hypernyms of particle include function word.

particle (noun)	closed-class word (noun)
a function word that can be used in English to form phrasal verbs	a word that is uninflected and serves a grammatical function but has little identifiable meaning
a body having finite mass and internal structure but negligible dimensions
(nontechnical usage) a tiny piece of anything