amateurism vs strong belief

amateurism and strong belief both are nouns.

Word	Noun	Adjective	Verb	Adverb
amateurism	Yes	No	No	No
strong belief	Yes	No	No	No

As nouns, strong belief is a hypernym of amateurism; that is, strong belief is a word with a broader meaning than amateurism:

amateurism: the conviction that people should participate in sports as a hobby (for the fun of it) rather than for money
strong belief: an unshakable belief in something without need for proof or evidence

Other hypernyms of amateurism include article of faith, conviction.

amateurism (noun)	strong belief (noun)
the conviction that people should participate in sports as a hobby (for the fun of it) rather than for money	an unshakable belief in something without need for proof or evidence