Riffraff
late 15th century (as riff and raff ): from Old French rif et raf ‘one and all, every bit’, of Germanic origin.
wiktionary
From Old French rif et raf(“one and all”), of Germanic origin. The first word is from rifler(“to scrape off”) and the last is from raffler, related to rafler(“to plunder”).
etymonline
riffraff (n.)
also riff-raff, late 15c., "persons of disreputable character or low degree," from earlier rif and raf (Anglo-French rif et raf) "one and all, everybody; every scrap, everything," also "sweepings, refuse, things of small value" (mid-14c.), from Old French rif et raf, from rifler "to spoil, strip" (see rifle (v.)). Second element from raffler "carry off," related to rafle "plundering," or from raffer "to snatch, to sweep together" (see raffle (n.)); the word presumably made more for suggestive half-rhyming alliteration than for sense.
The meaning "refuse, scum, or rabble of a community" is by 1540s. In 15c. collections of terms of association, a group of young men or boys was a raffle of knaves.
