Noted dukedom (4)
I believe the answer is:
york
'noted dukedom' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for york that I've seen before include "attempt to get out at the Oval" , "City and royal house" , "10 [HOUSE]" , "See bowl" , "Northern walled city" .)