Small hound
I believe the answer is:
'small hound' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for beagle that I've seen before include "Hunting dog followed on foot" , "Darwin voyaged in this ship" , "Small short-legged hound" , "5 [MANS BEST FRIEND]" , "Type of hound" .)