British naval hero (6)
I believe the answer is:
nelson
'british naval hero' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for nelson that I've seen before include "Admiral called 5" , "Noted English admiral" , "One-eyed English admiral seen on pillar" , "English admiral, mortally wounded at Trafalgar" , "Trafalgar victor" .)