Noble and key united game (7)
I believe the answer is:
duchess
'noble' is the definition.
(I've seen this before)
'key united game' is the wordplay.
'key' becomes 'd' (I've seen this in other clues).
'united' becomes 'u'.
'game' becomes 'chess' (chess game is a kind of game).
'd'+'u'+'chess'='DUCHESS'
'and' is the link.
(Other definitions for duchess that I've seen before include "Titled lady" , "Wife of a duke" , "Female aristocrat" , "title" , "Great lady" .)