bad luck vs toilet

bad luck and toilet both are nouns.

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

As nouns, toilet is a hyponym of bad luck; that is, toilet is a word with a more specific, narrower meaning than bad luck:

Other hyponyms of bad luck include weakness, adversity, hard knocks, hardship, gutter, sewer, hard cheese.

bad luck (noun)	toilet (noun)
unnecessary and unforeseen trouble resulting from an unfortunate event	the act of dressing and preparing yourself
an unpredictable outcome that is unfortunate	a room or building equipped with one or more toilets
an unfortunate state resulting from unfavorable outcomes	a plumbing fixture for defecation and urination
	misfortune resulting in lost effort or money