Boxer's ploy (5)
I believe the answer is:
feint
'boxer's ploy' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for feint that I've seen before include "ruled lightly" , "Sell a dummy" , "Deceptive movement designed to distract" , "Deceptive manoeuvre" , "False fencing trust sounds dim" .)