Meaning

noun a sharp abrupt noise as if two objects hit together; may be repeated

noun a simple valve with a hinge on one side; allows fluid to flow in only one direction

verb make a rattling sound

originFrom Middle English clacken, clakken, claken, from Old English *clacian (“to slap, clap, clack”), from Proto-Germanic *klakōną (“to clap, chirp”). Cognate with Scots clake, claik (“to utter cries", also "to bedaub, sully with a sticky substance”), Dutch klakken (“to clack, crack”), Low German klakken (“to slap on, daub”), Norwegian klakke (“to clack, strike, knock”), Icelandic klaka (“to twitter,…

Etymology from Wiktionary, CC BY-SA 3.0