No British film director admits married peer (8)
I believe the answer is:
nobleman
'peer' is the definition.
(I've seen this in another clue)
'no british film director admits married' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'film director' becomes 'lean' (David Lean).
'admits' indicates putting letters inside.
'married' becomes 'm'.
'lean' enclosing 'm' is 'leman'.
'no'+'b'+'leman'='NOBLEMAN'
(Other definitions for nobleman that I've seen before include "Titled person" , "Member of the aristocracy" , "Peer (of realm)" , "Male aristocrat" , "member of Upper House" .)