Contemptible sort (3)
I believe the answer is:
cur
'contemptible sort' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for cur that I've seen before include "Scoundrel; mongrel dog" , "Mongrel; rascal" , "Lowly dog" , "Mangy dog" , "Despicable person" .)