evil vs foul play

evil and foul play both are nouns.

Word	Noun	Adjective	Verb	Adverb
evil	Yes	Yes	No	No
foul play	Yes	No	No	No

As nouns, foul play is a hyponym of evil; that is, foul play is a word with a more specific, narrower meaning than evil:

Other hyponyms of evil include devilry, deviltry, irreverence, violation, sexual immorality.

evil (noun)	foul play (noun)
morally objectionable behavior	unfair or dishonest behavior (especially involving violence)
the quality of being morally wrong in principle or practice

evil (adjective)	foul play (adjective)
morally bad or wrong
having or exerting a malignant influence
having the nature of vice