A ruling on a point of Islamic law (5)
I believe the answer is:
fatwa
'a ruling on a point of islamic law' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fatwa that I've seen before include "threat" , "Legal ruling by Islamic leader, as against Salman Rushdie" , "Islamic sentence as on Salman Rushdie" , "Islamic opinion" , "Ruling by Islamic religious leader, as on Salman Rushdie" .)