Rebuked head of college concealed little boy (6)
I believe the answer is:
chided
'rebuked' is the definition.
(I've seen this before)
'head of college concealed little boy' is the wordplay.
'head of' indicates taking the first letters.
'concealed' becomes 'hid' ('hide' can be a synonym of 'conceal').
'little boy' becomes 'ed' (nickname or 'little' form of Edward).
The first letter of 'college' is 'c'.
'c'+'hid'+'ed'='CHIDED'
(Other definitions for chided that I've seen before include "Reprimanded or rebuked" , "Scolded or rebuked" .)