1610s, "cause to make a sharp, hard, metallic sound," perhaps echoic, perhaps a blend of clang (v.) and clink (v.), perhaps from a Low German source (compare Middle Dutch clank, Dutch klank, Old High German klanc, Middle Low German klank, German Klang). Intransitive sense "give out a clank" is from 1650s.
clank (n.)
"a sharp, hard, metallic sound," 1650s, from clank (v.). Reduplicated form clankety-clank attested from 1895.
the train clanked through the village
clan
clandestine
clang
clangor
clangorous
clank
clannish
clansman
clap
clapboard
clapper