Burning spirit (4)
I believe the answer is:
fire
This clue is a double definition.
'burning' is the first definition.
(I know that fire is a type of burning)
'spirit' is the second definition.
(thesaurus)
(Other definitions for fire that I've seen before include "cut" , "Flame - dismiss - shoot" , "Shoot; sack" , "Manually operated device for dealing with flames" , "See 5" .)