First to replace middle of song in poet, Owen's sort of rhyme gets help (10)
I believe the answer is:
assistance
'help' is the definition.
(synonyms)
'first to replace middle of song in poet owen's sort of rhyme' is the wordplay.
I cannot really understand how this works, but
'first' could be 'ist' (ist resembles 1st) and 'ist' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'gets' is the link.
(Other definitions for assistance that I've seen before include "Help" , "Aid" , "Support" .)