intj. (American).—An onomatopœia, representing, it is thought, the sound of an object falling heavily to the ground or into water.—See CACHUNK.
1835. HALIBURTON (‘Sam Slick’), The Clockmaker, 3 S., ch. ii. I felt … only one stop more [and I] was over head and ears CHEWALLOP in the water.
1888. HOPPE, Englisch-Deutsches Supplement-Lexikon, p. 215. It means ‘flat down,’ and is a strong expression. If a woman, for ex., falls head over heels and flat to the ground, they say, ‘she fell CHEWALLOP.’
