[1] : The Collaborative International Dictionary of English v.0.48

vacillation \vac`illa"tion\, n. l. vacillatio: cf. f.
   vacillation.
   1. the act of vacillating; a moving one way and the other; a
      wavering.
      1913 webster

            his vacillations, always exhibited most pitiably in
            emergencies.                          --macaulay.
      1913 webster

   2. unsteadiness of purpose; changeableness.
      1913 webster

            there is a vacillation, or an alternation of
            knowledge and doubt.                  --jer. taylor.
      1913 webster

[2] : WordNet (r) 2.0

vacillation
     n 1: indecision in speech or action syn: hesitation, wavering
     2: changing location by moving back and forth syn: swing, swinging
see also:
hesitation wavering swing swinging 

[3] : Moby Thesaurus II by Grady Ward, 1.0

66 moby thesaurus words for "vacillation":
   alternation, capriciousness, chance, chanciness, changeableness,
   dallying, demurral, dillydallying, equivocation, erraticism,
   erraticness, fickleness, fluctuation, frequency, frequency band,
   frequency spectrum, harmonic motion, hesitancy, hesitation,
   incalculability, incertitude, indecision, indecisiveness,
   indemonstrability, indeterminacy, indetermination, indeterminism,
   irresolution, libration, luck, nutation, oscillation, pendulation,
   periodicity, randomness, resonance, resonance frequency, seesawing,
   shifting, shilly-shally, shilly-shallying, shuffling, suspense,
   suspensefulness, teeter-tottering, teetering, tottering,
   unaccountability, uncertainness, uncertainty,
   uncertainty principle, undecidedness, undeterminedness,
   unforeseeableness, unpredictability, unprovability, unsureness,
   unverifiability, variation, vibrancy, vibratility, vibration,
   vicissitude, wavering, whimsicality, wobbling

Vacillation >> V Words
Vacillation, definition of term: Vacillation
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