RIFF-Raff,
the Rabble or Scum of the People, Tagrag and Longtail.
the Rabble or Scum of the People, Tagrag and Longtail.
Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
Riff Raff in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).