Temper in firepit (3)
I believe the answer is:
ire
'temper' is the definition.
(both can mean anger or rage)
'in firepit' is the wordplay.
'in' indicates the answer is hidden within the clue.
'IRE' is hidden in the letters of 'firepit'.
(Other definitions for ire that I've seen before include "Fury" , "Hot temper" , "passionate feeling" , "Displeasure" , "Strong feeling" .)