Grant, as president, lacking identity (7)
I believe the answer is:
present
'grant' is the definition.
(thesaurus)
'president lacking identity' is the wordplay.
'lacking' indicates named letters should be taken away.
'identity' becomes 'id' (I've seen this in other clues).
'president' with 'id' taken away is 'PRESENT'.
'as' is the link.
(Other definitions for present that I've seen before include "Christmas hand-out" , "In attendance with award?" , "Repents (anag.)" , "It is given" , "offering" .)