Large knife (7)
I believe the answer is:
machete
'large knife' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for machete that I've seen before include "Jungle blade" , "The mace (anag.)" , "Cheat me over broad heavy knife used in jungle" , "Heavy South American knife" , "Broad heavy knife used in S American jungles" .)