cargo vs shipment

cargo and shipment both are nouns.

Word	Noun	Adjective	Verb	Adverb
cargo	Yes	No	No	No
shipment	Yes	No	No	No

As nouns, cargo and shipment are synonyms defined as:

Other synonyms of cargo include consignment, freight, lading, load, loading, payload.

cargo (noun)	shipment (noun)
goods carried by a large vehicle	the act of sending off something
	goods carried by a large vehicle