Rotter (3)
'rotter' is the definition.
(a cad is a dishonourable person)
This is all the clue.
(Other definitions for cad that I've seen before include "One behaves dishonourably" , "An Englishman who behaves dishonourably, a rotter" , "Ungentlemanly person" , "A rotter, by Jove" , "Blackguard" .)
'rotter' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for bounder that I've seen before include "Dishonourable man (dated colloq.)" , "despicable man" , "Untrustworthy type (once)" , "The skipper" , "A cad - or a kind of jumper" .)