Opposite of haram (5)
I believe the answer is:
halal
'opposite of haram' is the definition.
(I know this)
This is all the clue.
(Other definitions for halal that I've seen before include "Meat fit for Muslims" , "(Meat) from animals slaughtered according to Muslim law" , "authorised food" , "Describing meat butchered according to Islamic law" , "which food is legal in Mecca" .)