calmcalmercalmest1adjective (calmer, calmest)pronunciationThe word calm sounds like arm, because we don't say the letter l in this word.1quiet, and not excited or afraid: Try to keep calm – there's no danger.2without big waves: a calm sea3without much wind: calm weather▶ calmlyadverb: He spoke calmly about the accident.calmcalmcalmscalmedcalming2verb (calms, calming, calmed)calm downto become less afraid or excited; to make somebody less afraid or excited: Calm down and tell me what happened.