riff-raff
Concise Oxford English Dictionary © 2008 Oxford University Press:
riff-raff/ˈrɪfraf/
▶noun disreputable or undesirable people.
– origin C15 (as riff and raff): from OFr. rif et raf ‘one and all, every bit’, of Gmc origin.
'riff-raff' also found in these Oxford entries:

