Vacillate rhymes with:
encapsulate, insulate, isolate, oscillate, tesselate, accumulate, adulate, annihilate, articulate, assimilate, calculate, circulate, coagulate, congratulate, copulate, correlate, crenelate, depopulate, distillate, emulate, encapsulate, escalate, extrapolate, flagellate, formulate, gastrulate, immolate, innoculate, inoculate, insulate, interpolate, isolate, lanceolate, manipulate, miscalculate, mutilate, oscillate, overregulate, percolate, populate, postulate, recalculate, recapitulate, reformulate, regulate, reregulate, speculate, stimulate, stipulate, strangulate, tabulate, tesselate, titillate, undulate, ventilate