ker-

ker-

an unstressed syllable prefixed to onomatopoeic and other expressive words, usu. forming adverbs or interjections: kerflop; kerplunk; ker-splosh.

Compare ca-

 [perhaps < Scots dial. car-, cur-, currie- (as in carfuffle, carwhuffle to disarrange), based on car, earlier ker left (hand or side) < Scottish Gaelic cearr wrong, awkward, left-handed]