good luck vs accident

good luck and accident both are nouns.

Word	Noun	Adjective	Verb	Adverb
good luck	Yes	No	No	No
accident	Yes	No	No	No

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

good luck: an unexpected piece of good luck
accident: anything that happens suddenly or by chance without an apparent cause

Other hypernyms of good luck include chance event, fortuity, stroke.

good luck (noun)	accident (noun)
an unexpected piece of good luck	anything that happens suddenly or by chance without an apparent cause
a stroke of luck	an unfortunate mishap; especially one causing damage or injury
an auspicious state resulting from favorable outcomes