Scold child with proof of age he's defaced (5)
I believe the answer is:
chide
'scold' is the definition.
(I know that scold can be written as chide)
'child with proof of age he's defaced' is the wordplay.
'child' becomes 'ch' (abbreviation for child).
'with proof of age' becomes 'id' (I can't explain this - if you can you should give a lot more credence to this answer).
'defaced' means to remove the first letter (the word with its face removed).
'he' with its initial letter taken away is 'e'.
'ch'+'id'+'e'='CHIDE'
Can you help me to learn more?
(Other definitions for chide that I've seen before include "Admonish" , "Tell off" , "Reprove" , "Censure angrily" , "lecture" .)