SS Orduña or Orduna was an ocean liner built in 1913–14 by Harland and Wolff in Belfast for the Pacific Steam Navigation Company. After two voyages she was chartered to Cunard Line. In 1921 she went to the Royal Mail Steam Packet Company, then being resold to the PSNCo in 1926. Her sister ships were Orbita and Orca. She provided transatlantic passenger transport, measured approximately 15,500 gross register tons, and was 550.3 ft x 67.3 ft.