sink vs come down

sink is a noun but come down is not a noun.

Word	Noun	Adjective	Verb	Adverb
sink	Yes	No	Yes	No
come down	No	No	Yes	No

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

Other hypernyms of sink include descend, fall, go down.

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

Other hypernyms of sink include descend, fall, go down.

sink (noun)	come down (noun)
plumbing fixture consisting of a water basin fixed to a wall or floor and having a drainpipe
a covered cistern; waste water and sewage flow into it
a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof
(technology) a process that acts to absorb or remove energy or a substance from a system

sink (verb)	come down (verb)
fall heavily or suddenly; decline markedly	get sick
embed deeply	be the essential element
go under	criticize or reprimand harshly
fall or descend to a lower place or level	move downward and lower, but not necessarily all the way
cause to sink	fall from clouds
fall or sink heavily
appear to move downward
descend into or as if into some soft substance or place
pass into a specified state or condition; sink into