fervour vs fever pitch

fervour and fever pitch both are nouns.

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

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

Other hyponyms of fervour include fever, sensation, feverishness.

fervour (noun)	fever pitch (noun)
feelings of great warmth and intensity	a state of extreme excitement
the state of being emotionally aroused and worked up