THESAURUS
vacillate
alternate, back and fill, bob, bobble, careen, change, changeable, chop and change, coggle, dally, dallying, dangle, demurring, dickey, dillydallying, dither, double-minded, doubtful, doubting, ebb and flow, eccentric, equivocate, erratic, falter, faltering, fickle, fiddle-faddle, flounder, fluctuant, fluctuate, fluctuating, flutter, go through phases, halt, halting, hang in doubt, hem and haw, hesitant, hesitate, hesitating, inconstant, indecisive, insecure, irresolute, librate, lurch, mercurial, nutate, oscillate, oscillating, pendulate, pendulous, pitch, reel, resonate, ring the changes, rock, roll, rootless, seesaw, shake, shaky, shift, shifting, shilly-shally, shilly-shallying, shuffle, stagger, stop to consider, swag, sway, swing, teeter, teeter-totter, tentative, tergiversate, think twice, timid, toss, totter, turn, uncertain, unresolved, unsettled, unstable, unsteady, unsure, vacillating, vacillatory, vary, vibrate, volatile, wag, waggle, wave, waver, wavering, wax and wane, weak, weak-kneed, whiffle, wigwag, wobble, wobbly
ROGET THESAURUS
vacillate
Tergiversation
VB
change one's mind, change one's intention, change one's purpose, change one's note, abjure, renounce, withdraw from, waver,
vacillate, wheel round, turn round, veer round, turn a pirouette, go over from one side to another, pass from one side to another, change from one side to another, skip from one side to another, go to the rightabout, box the compass, shift one's ground, go upon another tack, apostatize, change sides, go over, rat, recant, retract, revoke, rescind, recall, forswear, unsay, come over, come round to an opinion, crawfish, crawl, draw in one's horns, eat one's words, eat the leek, swallow the leek, swerve, flinch, back out of, retrace one's steps, think better of it, come back return to one's first love, turn over a new leaf, trim, shuffle, play fast and loose, blow hot and cold, coquet, be on the fence, straddle, bold with the hare but run with the hounds, nager entre deux eaux, wait to see how the cat jumps, wait to see how the wind blows.
Changeableness
VB
fluctuate, vary, waver, flounder, flicker, flitter, flit, flutter, shift, shuffle, shake, totter, tremble,
vacillate, wamble, turn and turn about, ring the changes, sway to and fro, shift to and fro, change and change about, waffle, blow with the wind (irresolute), oscillate, vibrate between, two extremes, oscillate between, two extremes, alternate, have as man phases as the moon.
Oscillation
VB
oscillate, vibrate, librate, alternate, undulate, wave, rock, swing, pulsate, beat, wag, waggle, nod, bob, courtesy, curtsy, tick, play, wamble, wabble, dangle, swag, fluctuate, dance, curvet, reel, quake, quiver, quaver, shake, flicker, wriggle, roll, toss, pitch, flounder, stagger, totter, move up and down, bob up and down, pass and repass, ebb and flow, come and go,
vacillate, teeter, brandish, shake, flourish.