fervour vs fever

fervour and fever both are nouns.

Word	Noun	Adjective	Verb	Adverb
fervour	Yes	No	No	No
fever	Yes	No	No	No

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

Other hyponyms of fervour include fever pitch, sensation, feverishness.

fervour (noun)	fever (noun)
feelings of great warmth and intensity	a state of nervous excitement
the state of being emotionally aroused and worked up	a rise in the temperature of the body; frequently a symptom of infection