Charybdis, Maelstrom, back stream, backflow, backwash, backwater, barf, countercurrent, counterflow, counterflux, disgorgement, doubling, duplication, echo, eddy, egesta, egestion, gagging, gulf, gurge, heaves, heaving, imitation, maelstrom, nausea, plagiarism, puke, quotation, reappearance, rebirth, recurrence, redoubling, reduplication, reecho, refluence, reflux, reincarnation, renewal, reoccurrence, repetition, reproduction, resumption, return, spew, swirl, twirl, vomit, vomiting, vomition, vortex, whirl, whirlpool