There's nothing in raising a blind (3)
I believe the answer is:
nil
'there's nothing' is the definition.
(nil means a score of zero in football)
'in raising a blind' is the wordplay.
'raising' says the letters should be written backwards.
'in' indicates the answer is hidden within the clue.
'lin' can be found hidden inside 'blind'.
'lin' written backwards gives 'NIL'.
(Other definitions for nil that I've seen before include "There's nothing left" , "Nothing, no score" , "Nothing - in Latin" , "Love" , "Lacking value" .)