Rapids rhymes with:
bicuspids, acids, antacids, arachnids, ballads, bicuspids, coloreds, desmids, fluids, gorrids, harrod's, harrods, hatreds, hundreds, hybrids, invalids, likud's, limited's, liquids, methods, miracid's, muhammad's, orchids, period's, periods, pleiads, preferreds, salads, solids, synod's, united's
Rapids sounds like:
rabbits, rafts, raptis, ravitch, ravitz, rebates, refutes, repeats, repetitious, repudiates, rifts, rivets, robidoux, robot's, robotic, robotics, robots