Bored with raw material (3)
I believe the answer is:
ore
'raw material' is the definition.
(I've seen this before)
'bored with' is the wordplay.
'with' indicates a hidden word.
'ORE' can be found hidden inside 'bored'.
(Other definitions for ore that I've seen before include "Unwrought iron" , "Raw iron" , "Mined material" , "Rock from which metal is extracted" , "Metal-bearing rock or mineral" .)