barterer vs trader

barterer and trader both are nouns.

Word	Noun	Adjective	Verb	Adverb
barterer	Yes	No	No	No
trader	Yes	No	No	No

As nouns, trader is a hypernym of barterer; that is, trader is a word with a broader meaning than barterer:

barterer: a trader who exchanges goods and not money
trader: someone who purchases and maintains an inventory of goods to be sold

Other hypernyms of barterer include bargainer, dealer, monger.

barterer (noun)	trader (noun)
a trader who exchanges goods and not money	someone who purchases and maintains an inventory of goods to be sold