homosexuality vs homosexualism

homosexuality and homosexualism both are nouns.

Word	Noun	Adjective	Verb	Adverb
homosexuality	Yes	No	No	No
homosexualism	Yes	No	No	No

As nouns, homosexuality and homosexualism are synonyms defined as:

homosexuality and homosexualism: a sexual attraction to (or sexual relations with) persons of the same sex

Other synonyms of homosexuality include gayness, homoeroticism, queerness.

homosexuality (noun)	homosexualism (noun)
a sexual attraction to (or sexual relations with) persons of the same sex	a sexual attraction to (or sexual relations with) persons of the same sex