Naughty child with a little dimple (3)
I believe the answer is:
imp
'naughty child' is the definition.
(informal term for a misbehaving child)
'with a little dimple' is the wordplay.
'with' indicates a hidden word.
'IMP' is hidden within 'little dimple'.
(Other definitions for imp that I've seen before include "Goblin" , "Pixie" , "A little devil of mischief" , "Sprite; add feathers to" , "A mischievous little devil" .)