Salty Greek cheese (4)
I believe the answer is:
feta
'salty greek cheese' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for feta that I've seen before include "Salty Greek cheese" , "White Greek cheese" , "Greek cheese from goat or sheep milk" , "White and salty goat or sheep cheese" , "Greek sheep or goats' cheese" .)