One using bait to trap chief hunting dog (7)
I believe the answer is:
lurcher
'hunting dog' is the definition.
(dog used on hunting trips)
'one using bait to trap chief' is the wordplay.
'one using bait' becomes 'lurer' (someone who lures using bait).
'to trap' indicates putting letters inside.
'chief' becomes 'ch' (abbreviation).
'lurer' enclosing 'ch' is 'LURCHER'.
(Other definitions for lurcher that I've seen before include "moving suddenly and unsteadily?" , "Crossbred dog similar to a greyhound" , "a hunting animal" , "The dog to stagger" , "canine cross?" .)