Fat used in candlemaking (4)
I believe the answer is:
suet
'fat used in candlemaking' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for suet that I've seen before include "Edible animal fat" , "Hard fat in cattle and sheep" , "Fatty stuff used in cooking" , "Edible fat used in cooking" , "Fat used in foods" .)