freight vs merchandise

freight and merchandise both are nouns.

Word	Noun	Adjective	Verb	Adverb
freight	Yes	No	Yes	No
merchandise	Yes	No	Yes	No

As nouns, merchandise is a hypernym of freight; that is, merchandise is a word with a broader meaning than freight:

Other hypernyms of freight include product, ware.

freight (noun)	merchandise (noun)
transporting goods commercially at rates cheaper than express rates	items for sale to the individual consumer
goods carried by a large vehicle	branded products meant to promote another product, especially films and pop groups
the charge for transporting something by common carrier

freight (verb)	merchandise (verb)
load with goods for transportation	engage in the trade of
transport commercially as cargo