Lord ahead of time? Not quite (4)
I believe the answer is:
earl
'lord' is the definition.
(earl is a kind of lord)
'ahead of time? not quite' is the wordplay.
'ahead of time?' becomes 'early' ('early' can be a synonym of 'ahead of time').
'not quite' means to remove the last letter (most but not all of the word).
'early' with its last letter taken away is 'EARL'.
(Other definitions for earl that I've seen before include "UK nobleman ranking between marquess and viscount" , "British peer and Dublin street" , "Male equivalent of a countess" , "Husband of a countess" , "Aristocrat ranking between marquis and viscount" .)