whoop it up vs roister

whoop it up and roister both are verbs.

Word	Noun	Adjective	Verb	Adverb
whoop it up	No	No	Yes	No
roister	No	No	Yes	No

As verbs, roister is a hyponym of whoop it up; that is, roister is a word with a more specific, narrower meaning than whoop it up:

whoop it up: celebrate noisily, often indulging in drinking; engage in uproarious festivities
roister: engage in boisterous, drunken merrymaking

Other hyponyms of whoop it up include carouse, riot.

whoop it up (verb)	roister (verb)
celebrate noisily, often indulging in drinking; engage in uproarious festivities	engage in boisterous, drunken merrymaking