vac·​il·​late | \ ˈva-sə-ˌlāt How to pronounce vacillate (audio) \
vacillated; vacillating

Definition of vacillate

intransitive verb

1 : to waver in mind, will, or feeling : hesitate in choice of opinions or courses
2a : to sway through lack of equilibrium

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Other Words from vacillate

vacillatingly \ ˈva-​sə-​ˌlā-​tiŋ-​lē How to pronounce vacillatingly (audio) \ adverb
vacillator \ ˈva-​sə-​ˌlā-​tər How to pronounce vacillator (audio) \ noun

Choose the Right Synonym for vacillate

hesitate, waver, vacillate, falter mean to show irresolution or uncertainty. hesitate implies a pause before deciding or acting or choosing. hesitated before answering the question waver implies hesitation after seeming to decide and so connotes weakness or a retreat. wavered in his support of the rebels vacillate implies prolonged hesitation from inability to reach a firm decision. vacillated until events were out of control falter implies a wavering or stumbling and often connotes nervousness, lack of courage, or outright fear. never once faltered during her testimony

Examples of vacillate in a Sentence

She has vacillated on this issue. vacillated for so long that someone else stepped in and made the decision

Recent Examples on the Web

Antiwar critics of Trump’s Jacksonian rhetoric turned on a dime to blast him as a weak, vacillating leader afraid to call Iran to account. Victor Davis Hanson, The Mercury News, "Hanson: Why the US can afford to stay calm with Iran," 27 June 2019 Everything happened so fast and vacillated between confusing, funny, and cringe-y. Emily Dreyfuss, WIRED, "Hollywood Tried to Save America with a Live Reading of the Mueller Report," 25 June 2019 Trump vacillated for months on whether to pick Shanahan, officials said. NBC News, "Trump may be having second thoughts about Shanahan as Defense Secretary," 11 June 2019 The appointments end a nearly two-week interregnum during which Mr. Macron and his prime minister vacillated, suggesting that Mr. Macron’s bench has become thin. Noemie Bisserbe, WSJ, "Macron, Under Pressure, Walks Tight Line With Cabinet Appointments," 16 Oct. 2018 His lingering opponent, Jamie Giellis vacillated, exposing weakness and inexperience. Doug Friednash, The Denver Post, "Friednash: Hancock’s victory in the face of uncertainty pales in comparison to the mayor’s other life challenges," 9 June 2019 And in a case that would have largely turned on Ms. Graswald’s vacillating statements, prosecutors also said that her admissions did not add up to a direct confession. Rick Rojas, New York Times, "Out of Prison, Fiancée in Kayak Case Says, ‘I’m Not Heartless’," 18 Feb. 2018 The deal follows months of vacillating over the East Coast Rail Link, which connects Malaysia’s west coast to eastern rural states and is a key part of China’s Belt and Road infrastructure initiative. Eileen Ng, The Seattle Times, "Malaysia revives China-backed rail link, cost cut by a third," 12 Apr. 2019 International observers say there’s no reason for Trump to vacillate. Karl Vick, Time, "To Nix or to Fix: Trump’s Major Dilemma on the Iran Deal," 3 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'vacillate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of vacillate

1597, in the meaning defined at sense 2a

History and Etymology for vacillate

borrowed from Latin vacillātus, past participle of vacillāre "to be unsteady, totter, be weak or inconstant, waver," of uncertain origin

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Statistics for vacillate

Last Updated

13 Jul 2019

Look-up Popularity

Time Traveler for vacillate

The first known use of vacillate was in 1597

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More Definitions for vacillate



English Language Learners Definition of vacillate

formal : to repeatedly change your opinions or desires


vac·​il·​late | \ ˈva-sə-ˌlāt How to pronounce vacillate (audio) \
vacillated; vacillating

Kids Definition of vacillate

: to hesitate between courses or opinions : be unable to choose

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Comments on vacillate

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something desired as essential

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