plunk vs place down

plunk is a noun but place down is not a noun.

Word	Noun	Adjective	Verb	Adverb
plunk	Yes	No	Yes	Yes
place down	No	No	Yes	No

As verbs, place down is a hypernym of plunk; that is, place down is a word with a broader meaning than plunk:

Other hypernyms of plunk include put down, set down.

plunk (noun)	place down (noun)
(baseball) hitting a baseball so that it drops suddenly
a hollow twanging sound

plunk (verb)	place down (verb)
pull lightly but sharply with a plucking motion	cause to sit or seat or be in a settled position or place
set (something or oneself) down with or as if with a noise
drop steeply
make or move along with a sound as of a horse's hooves striking the ground

plunk (adverb)	place down (adverb)
with a short hollow thud