Material for back fat cheese (7)
I believe the answer is:
taffeta
'material' is the definition.
(I know that taffeta is a type of material)
'back fat cheese' is the wordplay.
'back' says the letters should be written backwards.
'cheese' becomes 'feta' (type of cheese).
'fat' backwards is 'taf'.
'taf'+'feta'='TAFFETA'
'for' is the link.
(Other definitions for taffeta that I've seen before include "Lustrous silky fabric" , "A shiny silklike fabric" , "silky stuff" , "Fabric - fat fate (anag)" , "Crisp, smooth, lustrous fabric" .)