teetotalist vs abstainer

teetotalist and abstainer both are nouns.

Word	Noun	Adjective	Verb	Adverb
teetotalist	Yes	No	No	No
abstainer	Yes	No	No	No

As nouns, abstainer is a hypernym of teetotalist; that is, abstainer is a word with a broader meaning than teetotalist:

Other hypernyms of teetotalist include abstinent, nondrinker.

teetotalist (noun)	abstainer (noun)
a total abstainer	a person who refrains from drinking intoxicating beverages
	someone who practices self denial as a spiritual discipline