clunk

from WordNet (r) 3.0 (2006)

clunk
    n 1: a heavy dull sound (as made by impact of heavy objects)
         [syn: {thump}, {thumping}, {clump}, {clunk}, {thud}]
    v 1: make or move along with a sound as of a horse's hooves
         striking the ground [syn: {clop}, {clump}, {clunk},
         {plunk}]

from Moby Thesaurus II by Grady Ward, 1.0

25 Moby Thesaurus words for "clunk":
      bump, chink, click, clink, clop, clump, crump, dull thud, flick,
      flump, pad, pat, patter, pitapat, pitter-patter, plump, plunk, pop,
      rap, tap, thud, thump, tick, tinkle, tunk

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