There's nothing up in the ceiling (3)
I believe the answer is:
nil
'there's nothing' is the definition.
(nil means a score of zero in football)
'up in the ceiling' is the wordplay.
'up' is a reversal indicator (in down clue: letters go upwards).
'in' says the answer is hidden in the clue.
'lin' is hidden in the letters of 'ceiling'.
'lin' back-to-front is 'NIL'.
(Other definitions for nil that I've seen before include "Zero, no score" , "Zero, zilch" , "Latin zero" , "Nothing, zilch" , "Love" .)