Prawn or penguin? (4)

I believe the answer is:
king
(Other definitions for king that I've seen before include "and 21 Across: Shakespeare play" , "Court card" , "Male royal" , "Chesspiece which mustn't be lost" , "Man with a crown" .)
I believe the answer is:
king
(Other definitions for king that I've seen before include "and 21 Across: Shakespeare play" , "Court card" , "Male royal" , "Chesspiece which mustn't be lost" , "Man with a crown" .)