Oven used in roasting peanuts (4)
I believe the answer is:
oast
'oven' is the definition.
(type of kiln)
'in roasting peanuts' is the wordplay.
'in' says the answer is hidden in the clue.
'OAST' is hidden in the letters of 'roasting peanuts'.
'used' is the link.
(Other definitions for oast that I've seen before include "Cooker" , "Hop drying kiln" , "Hop-drier" , "Kiln for drying hops or malt" , "Where to cook" .)