Fit of ill-temper (7)
I believe the answer is:
tantrum
'fit of ill-temper' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for tantrum that I've seen before include "Fit of ill-temper" , "Pet, temper" , "Burst of rage" , "petulant outburst" , "Childish outbreak of temper" .)