sexual abuse vs sexual assault

sexual abuse and sexual assault both are nouns.

Word	Noun	Adjective	Verb	Adverb
sexual abuse	Yes	No	No	No
sexual assault	Yes	No	No	No

As nouns, sexual abuse and sexual assault are synonyms defined as:

sexual abuse and sexual assault: a statutory offense that provides that it is a crime to knowingly cause another person to engage in an unwanted sexual act by force or threat

Other synonyms of sexual abuse include sex crime, sex offense.

sexual abuse (noun)	sexual assault (noun)
a statutory offense that provides that it is a crime to knowingly cause another person to engage in an unwanted sexual act by force or threat	a statutory offense that provides that it is a crime to knowingly cause another person to engage in an unwanted sexual act by force or threat