Rabble (4-4)

I believe the answer is:
riff-raff
'rabble' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for riff-raff that I've seen before include "Hoi polloi" , "Undesirables" , "Disreputable people" , "Rabble" , "Dregs of society" .)