plunk vs go down

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

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

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

Other hypernyms of plunk include come down, descend, fall.

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

plunk (verb)	go down (verb)
pull lightly but sharply with a plucking motion	grow smaller
set (something or oneself) down with or as if with a noise	stop operating
drop steeply	be defeated
make or move along with a sound as of a horse's hooves striking the ground	be ingested
	go under
	disappear beyond the horizon
	move downward and lower, but not necessarily all the way
	be recorded or remembered

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