D defs.my
Entry 2 senses Webster, 1913

Vacillate

/(văs"ĭl*lāt)/ · Vac·il·late · IPA /ˈvæ.sə.leɪt/
01 v. i. To move one way and the other; to reel or stagger; to waver.
imp. & p. p. Vacillated; p. pr. & vb. n. Vacillating
  1. 1.
    To move one way and the other; to reel or stagger; to waver.
    “[A spheroid] is always liable to shift and vacillatefrom one axis to another.” — Paley.
  2. 2.
    To fluctuate in mind or opinion; to be unsteady or inconstant; to waver.
Syn. See Fluctuate.