delirium vs folie

delirium and folie both are nouns.

Word	Noun	Adjective	Verb	Adverb
delirium	Yes	No	No	No
folie	Yes	No	No	No

As nouns, folie is a hypernym of delirium; that is, folie is a word with a broader meaning than delirium:

delirium: a usually brief state of excitement and mental confusion often accompanied by hallucinations
folie: (psychiatry) a psychological disorder of thought or emotion; a more neutral term than mental illness

Other hypernyms of delirium include disturbance, mental disorder, mental disturbance, psychological disorder.

delirium (noun)	folie (noun)
a usually brief state of excitement and mental confusion often accompanied by hallucinations	(psychiatry) a psychological disorder of thought or emotion; a more neutral term than mental illness
state of violent mental agitation