noun
historicalIn the 18th century: a Spanish ship with a special licence authorizing it to trade outside the fleet system with the Spanish possessions in America, in specified areas or countries.
The cargo of a register ship had to be specified to the Board of Trade, the body controlling all Spanish trade with the West Indies, according to both nature and volume.
Origin
Early 18th century; earliest use found in Account Cruelties by Inquisition in Portugal. From register + ship, after Spanish navío de registro.
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