Spoilt little brat put on display (8)
I believe the answer is:
impaired
'spoilt' is the definition.
('impair' can be a synonym of 'spoil')
'little brat put on display' is the wordplay.
'little brat' becomes 'imp' (I've seen this in another clue).
'put' indicates putting letters inside.
'on' becomes 're' ('on' can be mean 'with reference to').
'display' becomes 'aid' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
're' going into 'aid' is 'aired'.
'imp'+'aired'='IMPAIRED'
Can you help me to learn more?
(Other definitions for impaired that I've seen before include "Made worse or less effective" , "Defective" , "casued damage" , "Had negative impact" , "Spoilt" .)