TSS Manxman was a turbine steamer launched in 1904 for the Midland Railway and operated between Heysham and Douglas, Isle of Man. In 1916, she was commissioned by the Royal Navy as HMS Manxman and saw action as a seaplane carrier during the First World War, after which she was acquired by the Isle of Man Steam Packet Company. On the outbreak of World War II she was again requisitioned as a troop ship, until she was commissioned and her name changed to HMS Caduceus. She never returned to Manx waters, and was scrapped in August 1949.