plunk (Noun) — A hollow twanging sound.
plunk (Noun) — (baseball) hitting a baseball so that it drops suddenly.
plunk (Verb) — Make or move along with a sound as of a horse's hooves striking the ground.
plunk (Verb) — Set (something or oneself) down with or as if with a noise. ex. "He plunked the money on the table"
plunk (Verb) — Drop steeply. ex. "the stock market plunked"
plunk (Verb) — Pull lightly but sharply with a plucking motion. ex. "he plunked the strings of his mandolin"
plunk (Adverb) — With a short hollow thud. ex. "plunk came the ball down to the corner of the green"