fire-swallower vs fire-eater

fire-swallower and fire-eater both are nouns.

Word	Noun	Adjective	Verb	Adverb
fire-swallower	Yes	No	No	No
fire-eater	Yes	No	No	No

As nouns, fire-swallower and fire-eater are synonyms defined as:

fire-swallower (noun)	fire-eater (noun)
a performer who pretends to swallow fire	a performer who pretends to swallow fire
	a belligerent grouch
	a member of a fire department who tries to extinguish fires