RAPID is validvalid

fast-moving [adj RAPIDER, RAPIDEST] : RAPIDLY [adv], RAPIDNESS [n] / a fast-moving part of a river [n RAPIDS]

11,971 of 196,601 in NWL2023·also valid in CSW24

quick [adj RAPIDER, RAPIDEST, RAPIDLY] / a swift-flowing part of a river [n -S]