misadventure vs bad luck

misadventure and bad luck both are nouns.

Word	Noun	Adjective	Verb	Adverb
misadventure	Yes	No	No	No
bad luck	Yes	No	No	No

As nouns, bad luck is a hypernym of misadventure; that is, bad luck is a word with a broader meaning than misadventure:

misadventure: an instance of misfortune
bad luck: unnecessary and unforeseen trouble resulting from an unfortunate event

Other hypernyms of misadventure include misfortune.

misadventure (noun)	bad luck (noun)
an instance of misfortune	unnecessary and unforeseen trouble resulting from an unfortunate event
	an unpredictable outcome that is unfortunate
	an unfortunate state resulting from unfavorable outcomes