plunk

Etymology

Onomatopoeic; the noun is attested earlier than the verb. Noun etymology 1, noun sense 3 (“dollar; large sum of money”) may refer to the sound of a coin hitting a surface. Compare plonk, plink. As regards verb etymology 1, verb sense 1.4 (“(transitive) to drop, set, or throw (something, or oneself) abruptly and/or heavily”) and etymology 1, verb sense 2.4 (“(intransitive) to drop, land, or set abruptly and/or heavily”), compare French plonquer (Picardy), a variant of plonger (“to plunge”).