Wrong leaf's blown (5)
I believe the answer is:
false
'wrong' is the definition.
(associated in meaning)
'leaf's blown' is the wordplay.
'blown' indicates anagramming the letters (to blow can mean to disrupt or scatter).
'leafs' with letters rearranged gives 'FALSE'.
(Other definitions for false that I've seen before include "Misleading" , "Not genuine or real" , "Artificial" , "Mendacious" , "Forged" .)