Expressive (adjective)
Effectively conveying thought or feeling.
Expressive (noun)
Any word or phrase that expresses (that the speaker, writer, or signer has) a certain attitude toward or information about the referent.
Expressive (noun)
A word or phrase, belonging to a distinct word class or having distinct morphosyntactic properties, with semantic symbolism (for example, an onomatopoeia), variously considered either a synonym, a hypernym or a hyponym of ideophone.
Eloquent (adjective)
fluently persuasive and articulate
Eloquent (adjective)
effective in expressing meaning by speech
Wiktionary