Definitely not many bones broken (2,2,5)
I believe the answer is:
by no means
'definitely not' is the definition.
(I've seen this before)
'many bones broken' is the wordplay.
'broken' is an anagram indicator.
'many'+'bones'='manybones'
'manybones' is an anagram of 'BY NO MEANS'.
(Other definitions for by no means that I've seen before include "Without using any method" , "Certainly not, perish the thought" , "Forbids" , "Definitely not" , "Certainly not, not in any way" .)