mania vs delirium

mania and delirium both are nouns.

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

As nouns, delirium is a hyponym of mania; that is, delirium is a word with a more specific, narrower meaning than mania:

mania: a mood disorder; an affective disorder in which the victim tends to respond excessively and sometimes violently
delirium: state of violent mental agitation

Other hyponyms of mania include craze, frenzy, fury, hysteria.

mania (noun)	delirium (noun)
an irrational but irresistible motive for a belief or action	a usually brief state of excitement and mental confusion often accompanied by hallucinations
a mood disorder; an affective disorder in which the victim tends to respond excessively and sometimes violently	state of violent mental agitation