1796, "to make the sound of a cork being pulled from a bottle;" imitative. This was the main sense through most of 19c. Meaning "to hit, strike" is attested from 1943 (perhaps a variant of clonk). Related: Clunked; clunking. As a noun, in reference to the cork-pulling sound, by 1823.
clump
clumperton
clumpy
clumsy
clung
clunk
clunker
clunky
cluster
clusterfuck
clutch