sea rover

noun3

1. •
   One who travels the ocean; one who spends a great deal of time at sea.

   • Then down the brave man lay with his bolster under his head and his whole company of sea-rovers at rest beside him. — 1999
2. •
   A pirate, buccaneer or privateer; an ocean-going marauder.

   • The turning of your ship into a sea-rover would have made the entire ocean a scene of outrage, rapine, and murder. — 1843
3. •
   (informal, no longer used) A herring.