The order for silence, treat rebelliously and break (7)
I believe the answer is:
shatter
'break' is the definition.
(to break can mean to shatter)
'the order for silence treat rebelliously' is the wordplay.
'the order for silence' becomes 'sh' (I am not sure about this - if you are sure you should believe this answer much more).
'rebelliously' is an anagram indicator.
'treat' with letters rearranged gives 'atter'.
'sh'+'atter'='SHATTER'
'and' acts as a link.
Can you help me to learn more?
(Other definitions for shatter that I've seen before include "Break suddenly" , "Break into many pieces" , "thoroughly upset" , "Threats (anag.)" , "Ruin" .)