monger vs merchant

monger and merchant both are nouns.

Word	Noun	Adjective	Verb	Adverb
monger	Yes	No	Yes	No
merchant	Yes	No	No	No

As nouns, merchant is a hypernym of monger; that is, merchant is a word with a broader meaning than monger:

monger: someone who purchases and maintains an inventory of goods to be sold
merchant: a businessperson engaged in retail trade

Other hypernyms of monger include merchandiser.

monger (noun)	merchant (noun)
someone who purchases and maintains an inventory of goods to be sold	a businessperson engaged in retail trade

monger (verb)	merchant (verb)
sell or offer for sale from place to place