vanish vs bob under

vanish and bob under both are verbs.

Word	Noun	Adjective	Verb	Adverb
vanish	No	No	Yes	No
bob under	No	No	Yes	No

As verbs, bob under is a hyponym of vanish; that is, bob under is a word with a more specific, narrower meaning than vanish:

Other hyponyms of vanish include dematerialise, dematerialize, clear.

vanish (verb)	bob under (verb)
get lost, as without warning or explanation	disappear suddenly, as if under the surface of a body of water
decrease rapidly and disappear
cease to exist
pass away rapidly
become invisible or unnoticeable