faithful vs fidelity

faithful and fidelity both are nouns.

Word	Noun	Adjective	Verb	Adverb
faithful	Yes	Yes	No	No
fidelity	Yes	No	No	No

faithful (noun)	fidelity (noun)
a group of people who adhere to a common faith and habitually attend a given church	the quality of being faithful
any loyal and steadfast following	accuracy with which an electronic system reproduces the sound or image of its input signal

faithful (adjective)	fidelity (adjective)
steadfast in affection or allegiance
not having sexual relations with anyone except your husband or wife, or your boyfriend or girlfriend
marked by fidelity to an original