arousal vs sex activity

arousal and sex activity both are nouns.

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

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

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

arousal (noun)	sex activity (noun)
the act of arousing	activities associated with sexual intercourse
mutual sexual fondling prior to sexual intercourse
awakening from sleep
a state of heightened physiological activity