Baptist vs Dunkard

Baptist and Dunkard both are nouns.

Word	Noun	Adjective	Verb	Adverb
Baptist	Yes	No	No	No
Dunkard	Yes	No	No	No

As nouns, Dunkard is a hyponym of Baptist; that is, Dunkard is a word with a more specific, narrower meaning than Baptist:

Baptist: follower of Baptistic doctrines
Dunkard: an adherent of Baptistic doctrines (who practice baptism by immersion)

Other hyponyms of Baptist include Dunker, Tunker, Northern Baptist, Southern Baptist.

Baptist (noun)	Dunkard (noun)
follower of Baptistic doctrines	an adherent of Baptistic doctrines (who practice baptism by immersion)