rapid /ˈɹæp.ɪd/adjective 5noun 3adverb 1forms 5 adjective5 •Very swift or quick.Ascend my Chariot; guide the rapid Wheeles. — 1667 •Steep, changing altitude quickly. (of a slope) •Needing only a brief exposure time. (of a lens, plate, film, etc.) •(dialect) Violent, severe. •(dialect, no longer used) Happy. noun3 •[usually plural] A rough section of a river or stream which is difficult to navigate due to the swift and turbulent motion of the water. •Ellipsis of rapid chess.In these rapid games we had just twenty-five minutes each to make all our moves, a far cry from traditional chess, where games can last up to seven hours. — 2010 •(old-fashioned) A burst of rapid fire. adverb1 •(informal, no longer used) Rapidly. formsrapids · more rapid · rapider · most rapid · rapidest