supracargo

noun2

1. •
   (historical) An officer on board a merchant ship who is in charge of the cargo and its sale; also, if there are two of such officers, the senior one, the other being the subcargo.

   • [S]he vvill let a Man freely enter, so that he be no Piqueroon or Caper, but an honest Merchant, that vvill not only largely pay for the Freight, but make her Supracargo too. — 1675
2. •
   (no longer used) An agent or representative of a company in charge of its overseas business.