chastity vs sexual abstention

chastity and sexual abstention both are nouns.

Word	Noun	Adjective	Verb	Adverb
chastity	Yes	No	No	No
sexual abstention	Yes	No	No	No

As nouns, chastity and sexual abstention are synonyms defined as:

chastity and sexual abstention: abstaining from sexual relations (as because of religious vows)

Other synonyms of chastity include celibacy.

chastity (noun)	sexual abstention (noun)
abstaining from sexual relations (as because of religious vows)	abstaining from sexual relations (as because of religious vows)
morality with respect to sexual relations