Stops breaking poles (5)
I believe the answer is:
posts
'poles' is the definition.
'stops breaking' is the wordplay.
'breaking' indicates anagramming the letters.
'stops' with letters rearranged gives 'POSTS'.
(Other definitions for posts that I've seen before include "Mails the uprights?" , "Is dispatching" , "a couple seen propping up the bar?" , "Stakes" , "Jobs and poles" .)