buoy up vs hold up

buoy up and hold up both are verbs.

Word	Noun	Adjective	Verb	Adverb
buoy up	No	No	Yes	No
hold up	No	No	Yes	No

As verbs, hold up is a hypernym of buoy up; that is, hold up is a word with a broader meaning than buoy up:

Other hypernyms of buoy up include hold, support, sustain.

buoy up (verb)	hold up (verb)
become more cheerful	cause to be slowed down or delayed
keep afloat	be the physical support of; carry the weight of
make more cheerful	hold up something as an example; hold up one's achievements for admiration
	rob at gunpoint or by means of some other threat
	continue to live and avoid dying
	resist or withstand wear, criticism, etc.
	resist or confront with resistance