Gun clip
I believe the answer is:
bulldog
This clue is a double definition.
'gun' is the first definition.
(thesaurus)
'clip' is the second definition.
(bulldog clip is a kind of clip)
(Other definitions for bulldog that I've seen before include "Kind of clip" , "British canine emblem" , "Canine (with British spirit?)" , "Courageous canine - clip" , "Breed of canine; stationery clip" .)