Adverb
An adverb was a word that modified verbs, adjectives and other adverbs.
In 2152, Hoshi Sato provided a translation of the Retellian language to Trip Tucker, and reasoned that it was fairly accurate, "give or take an adverb". (ENT: "Precious Cargo")
In 2376, Kathryn Janeway said she would rather be "tracking Ransom, not tinkering with [the] adverbs" in a message constructed to communicate with nucleogenic lifeforms. (VOY: "Equinox, Part II")