in Grammar, a particle joined to a verb, adjective, or participle, to explain their manner of acting or suffering, or to mark some circumstance or quality signified by them. The word is formed from the preposition ad, to, and verbum, a verb; and signifies literally a word joined to a verb, to show how, when, or where, one is, does, or suffers; as, the boy paints neatly, writes ill; the house stands there, &c.