sea king

from WordNet (r) 3.0 (2006)

sea king
    n 1: a Viking pirate chief

from The Collaborative International Dictionary of English v.0.48

Sea king \Sea" king`\
   One of the leaders among the Norsemen who passed their lives
   in roving the seas in search of plunder and adventures; a
   Norse pirate chief. See the Note under {Viking}.
   [1913 Webster]