Smells 50% of food belonging to us (6)
I believe the answer is:
odours
'smells' is the definition.
('odour' can be a synonym of 'smell')
'50% of food belonging to us' is the wordplay.
'50% of' suggests halving the letters.
'belonging to us' becomes 'ours' (I've seen this before).
'food' halved is 'od'.
'od'+'ours'='ODOURS'
(Other definitions for odours that I've seen before include "Smells and fragrances" , "emanations" , "Smells, redolences" , "for the nose to detect" , "Smells of any kind" .)