Troublemaker sacked for pinching grain husks (9)
I believe the answer is:
firebrand
'troublemaker' is the definition.
(thesaurus)
'sacked for pinching grain husks' is the wordplay.
'sacked' becomes 'fired' (both can mean dismissed from a job).
'for pinching' indicates putting letters inside (some letters pinch or steal others).
'grain husks' becomes 'bran' (I've seen this before).
'fired' placed around 'bran' is 'FIREBRAND'.
(Other definitions for firebrand that I've seen before include "Agitator" , "One who stirs up trouble" , "Rabble-rouser" , "Energetic person often fomenting trouble" , "Troublemaker" .)