[ vas-uh-leyt ]
See synonyms for: vacillatevacillatesvacillating on

verb (used without object),vac·il·lat·ed, vac·il·lat·ing.
  1. to waver in mind or opinion; be indecisive or irresolute: His tendency to vacillate makes him a poor leader.

  2. to sway unsteadily; waver; totter; stagger.

  1. to oscillate or fluctuate.

Origin of vacillate

First recorded in 1590–1600; from Latin vacillātus (past participle of vacillāre “to sway to and fro”); see -ate1

synonym study For vacillate

1. See waver1.

Other words for vacillate

Other words from vacillate

  • vac·il·la·tor, noun

Words Nearby vacillate Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use vacillate in a sentence

British Dictionary definitions for vacillate


/ (ˈvæsɪˌleɪt) /

  1. to fluctuate in one's opinions; be indecisive

  2. to sway from side to side physically; totter or waver

Origin of vacillate

C16: from Latin vacillāre to sway, of obscure origin

Derived forms of vacillate

  • vacillation, noun
  • vacillator, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012