On the whole, danger ably diverted (2,3,5)
I believe the answer is:
by and large
'on the whole' is the definition.
(both can mean 'generally')
'danger ably diverted' is the wordplay.
'diverted' is an anagram indicator (each letter get diverted elsewhere).
'danger'+'ably'='dangerably'
'dangerably' is an anagram of 'BY AND LARGE'.
(Other definitions for by and large that I've seen before include "for the most part" , "Speaking generally" , "All things considered" , "On the whole" , "In the main" .)