The Duke of Edinburgh (6)
I believe the answer is:
philip
'the duke of edinburgh' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for philip that I've seen before include "Duke of Edinburgh, say" , "Boy's name" , "--- of Macedon; --- Pirrip (Dickens)" , "Best Actor Oscar winner 2005, for 'Capote'" , "From leader of Spain" .)