weakness vs bad luck

weakness and bad luck both are nouns.

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

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

Other hypernyms of weakness include ill luck, misfortune, tough luck.

weakness (noun)	bad luck (noun)
the property of lacking physical or mental strength; liability to failure under pressure or stress or strain	unnecessary and unforeseen trouble resulting from an unfortunate event
powerlessness revealed by an inability to act	an unpredictable outcome that is unfortunate
a penchant for something even though it might not be good for you	an unfortunate state resulting from unfavorable outcomes
a flaw or weak point
the condition of being financially weak