Despicable fellow (3)
(Other definitions for cur that I've seen before include "Vicious dog" , "Mangy dog" , "Non-pedigree dog" , "Despicable person" , "A worthless dog or contemptible person" .)
'despicable fellow' is the definition.
(rat can mean a despicable person)
This is the entire clue.
(Other definitions for rat that I've seen before include "Treacherous rodent" , "Grass" , "Inform" , "Tell-tale" , "that gets out of stricken vessel" .)
'despicable fellow' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rotter that I've seen before include "Absolute bounder" , "Bad guy" , "Rogue" , "One not to be honoured" , "baddie" .)