Pet insect runs in bread basket (7)
I believe the answer is:
tantrum
'pet' is the definition.
(I've seen this before)
'insect runs in bread basket' is the wordplay.
'insect' becomes 'ant' (ant is a kind of insect).
'runs' becomes 'r' (cricket abbreviation).
'in' means one lot of letters goes inside another.
'bread basket' becomes 'tum' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ant'+'r'='antr'
'antr' placed within 'tum' is 'TANTRUM'.
Can you help me to learn more?
(Other definitions for tantrum that I've seen before include "Fit of childish temper" , "Childish angry outburst" , "Burst of temper" , "Display of bad temper" , "Hissy fit" .)