Hunting hound (6)
I believe the answer is:
'hunting hound' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for beagle that I've seen before include "Short-haired dog" , "HMS - was Darwin's ship; hunting dog" , "Small, sturdy breed of hound" , "hunting animal with smooth coat" , "Hunting hound" .)