Synonyms and related words :
bump, cave, cave in, chink, click, clink, clop, clump, clunk, crump, decline, droop, dull thud, flick, flop, flop down, flump down, founder, give way, go down, lapse, lower, pad, pat, patter, pitapat, pitter-patter, plop, plop down, plump, plunk, pop, rap, sag, set, settle, settle down, sink, sink down, slouch, slump, slump down, submerge, subside, swag, tap, thud, thump, tick, tinkle, tunk