Definition of CONTRACT CARRIER. : a transport line that carries persons or property under contract to one or a limited number of shippers — compare common carrier.ADVERTISEMENT. This word doesn't usually appear in our free dictionary, but the definition from our premium Unabridged Dictionary is offered here on a limited basis.ote that some information is displayed differently in the Unabridged. To access the complete Unabridged Dictionary, with an additional 300,000 words that aren't in our free dictionary, start a free trial.