sewer vs bad luck

sewer and bad luck both are nouns.

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

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

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

sewer (noun)	bad luck (noun)
a waste pipe that carries away sewage or surface water	unnecessary and unforeseen trouble resulting from an unfortunate event
misfortune resulting in lost effort or money	an unpredictable outcome that is unfortunate
someone who sews	an unfortunate state resulting from unfavorable outcomes