Rotter (3)

I believe the answer is:
cad
'rotter' is the definition.
(I've seen this in another clue)
This is the entire 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" .)