"Metropolis" director (4)
I believe the answer is:
lang
'metropolis director' is the definition.
(Fritz Lang, director of the 1927 film Metropolis)
This is the entire clue.
(Other definitions for lang that I've seen before include "Austrian-born film director" , "Traditional Scottish song 'Auld . . . . Syne'" , "Old song 'Auld . . . . Syne'" .)