Mormon vs Latter-Day Saint

Mormon and Latter-Day Saint both are nouns.

Word	Noun	Adjective	Verb	Adverb
Mormon	Yes	Yes	No	No
Latter-Day Saint	Yes	No	No	No

As nouns, Mormon and Latter-Day Saint are synonyms defined as:

Mormon and Latter-Day Saint: a member of the Church of Jesus Christ of Latter-Day Saints

Mormon (noun)	Latter-Day Saint (noun)
the ancient prophet whose writings were revealed to Joseph Smith who founded the Church of Jesus Christ of Latter-Day Saints	a member of the Church of Jesus Christ of Latter-Day Saints
a member of the Church of Jesus Christ of Latter-Day Saints

Mormon (adjective)	Latter-Day Saint (adjective)
of or pertaining to or characteristic of the Mormon Church