monotheist vs worshipper

monotheist and worshipper both are nouns.

Word	Noun	Adjective	Verb	Adverb
monotheist	Yes	No	No	No
worshipper	Yes	No	No	No

As nouns, worshipper is a hypernym of monotheist; that is, worshipper is a word with a broader meaning than monotheist:

Other hypernyms of monotheist include believer, worshiper.

monotheist (noun)	worshipper (noun)
a believer in one god	a person who has religious faith
	someone who admires too much to recognize faults