quiescentEnglishOxford English Thesaurusquiescent adjective the volcano is in a quiescent state: inactive, inert, latent, fallow, passive, idle, at rest, inoperative, deactivated, in abeyance, quiet; still, motionless, immobile, stagnant, dormant, asleep, slumbering, sluggish, lethargic, torpid. ▷antonyms active.quiescent Oxford Dictionary of English