go under vs go down

go under and go down both are verbs.

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

As verbs, go under and go down are synonyms defined as:

Other synonyms of go under include settle, sink.

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

Other hypernyms of go under include come down, descend, fall.

As verbs, go under and go down are synonyms defined as:

Other synonyms of go under include set.

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

Other hypernyms of go under include come down, descend, fall.

go under (verb)	go down (verb)
be called; go by a certain name	grow smaller
go under	stop operating
disappear beyond the horizon	be defeated
	be ingested
	go under
	disappear beyond the horizon
	move downward and lower, but not necessarily all the way
	be recorded or remembered