Child's original feature? (6)
I believe the answer is:
urchin
'child's' is the definition.
(urchin is a kind of child)
'original feature?' is the wordplay.
'original' becomes 'ur'.
'feature?' becomes 'chin' (chin is a kind of feature).
'ur'+'chin'='URCHIN'
(Other definitions for urchin that I've seen before include "Ragged child; marine animal" , "Hedgehog - ragamuffin" , "Monkey" , "Mischievous child and hedgehog" , "Mischievous or ragged child" .)