Definition of vacillatenext

Synonym Chooser

How does the verb vacillate differ from other similar words?

Some common synonyms of vacillate are falter, hesitate, and waver. While all these words mean "to show irresolution or uncertainty," vacillate implies prolonged hesitation from inability to reach a firm decision.

vacillated until events were out of control

When is it sensible to use falter instead of vacillate?

While the synonyms falter and vacillate are close in meaning, falter implies a wavering or stumbling and often connotes nervousness, lack of courage, or outright fear.

never once faltered during her testimony

When would hesitate be a good substitute for vacillate?

The words hesitate and vacillate are synonyms, but do differ in nuance. Specifically, hesitate implies a pause before deciding or acting or choosing.

hesitated before answering the question

When could waver be used to replace vacillate?

Although the words waver and vacillate have much in common, waver implies hesitation after seeming to decide and so connotes weakness or a retreat.

wavered in his support of the rebels

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of vacillate How power should be divided among the legislative, judicial, and executive branches of government has defined the American experiment, with power swinging pendulum-like between the branches without ever vacillating too far in one direction. Henry Gass, Christian Science Monitor, 14 June 2026 In general, game-to-game data vacillates pretty wildly. Sahadev Sharma, New York Times, 2 June 2026 And Dylan vacillates in that same way. Stuart Miller, Oc Register, 1 June 2026 Faced with a tough decision, Chiles vacillated. Miami Herald, 31 May 2026 See All Example Sentences for vacillate
Recent Examples of Synonyms for vacillate
Verb
  • And women who suspect their period pain is more severe than normal should not hesitate to speak with a health care provider, especially if symptoms are affecting their quality of life.
    Daryl Austin, USA Today, 7 July 2026
  • In the second half, Freese stepped off his line to control a ball, hesitated, stubbed his foot against the ground, and lost the ball.
    Louisa Thomas, New Yorker, 7 July 2026
Verb
  • Current training methods, such as reinforcement learning, can produce robots that are very good at consistently performing a specific task under very specific conditions—but such robots may falter on the same task under different conditions.
    Jeremy Hsu, ArsTechnica, 7 July 2026
  • Without this common utility, even the most complex of war machines will falter.
    Christopher McFadden, Interesting Engineering, 6 July 2026

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Cite this Entry

“Vacillate.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/vacillate. Accessed 10 Jul. 2026.

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