bisexuality vs sex activity

bisexuality and sex activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
bisexuality	Yes	No	No	No
sex activity	Yes	No	No	No

As nouns, sex activity is a hypernym of bisexuality; that is, sex activity is a word with a broader meaning than bisexuality:

Other hypernyms of bisexuality include sex, sexual activity, sexual practice.

bisexuality (noun)	sex activity (noun)
sexual activity with both men and women	activities associated with sexual intercourse
showing characteristics of both sexes