See vacillate in Webster's New World Roget's A-Z Thesaurus II
verb
To move back and forth or from side to side, as if about to fall:
sway, teeter, totter, waver, weave, wobble. See repetitionTo be irresolute in acting or doing:
dither, falter, halt2, hesitate, pause, shilly-shally, stagger, waver, wobble. See decideTo change one's attitudes or policies, for example:
swing, waver. See change, decide
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