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

In later years, Frank vacillated between photography and filmmaking, earning solo exhibitions at the National Gallery of Art and the Tate Modern. Emma Specter, Vogue, "Photographer Robert Frank is Dead at 94," 10 Sep. 2019 Opponents at the time included Kirsten Gillibrand, then a member of the House of Representatives; Hillary Clinton, who vacillated on the issue then came out against it; and Lt. Vivian Wang, New York Times, "Progressives Vowed Driver’s Licenses for the Undocumented. Then the Suburbs Spoke Up.," 16 June 2019 Russia itself has vacillated in its official response, calling to mind the Chernobyl disaster with decisions to initially censor radiation reports before admitting the test accident. Tim Fernholz, Quartz, "Russia’s nuclear-powered doomsday missile, explained," 13 Aug. 2019 Carlos, who vacillated daily between hope and despair, thanked Peña for her efforts. Melissa Del Bosque, ProPublica, "The Case That Made an Ex-ICE Attorney Realize the Government Was Relying on False “Evidence” Against Migrants," 13 Aug. 2019 Auburn’s place within the college football pecking order vacillates wildly. Christopher Smith, al, "Auburn’s running game will determine the Tigers’ 2019 betting value," 21 Aug. 2019 The home quietly vacillates between high-glam and lived-in—a space distinctly her own, designed on her own terms. Lucia Tonelli, ELLE Decor, "Inside a Chanel Fashion Executive’s High-Glam Sutton Place Home," 26 July 2019 This month, Burrell and Goodrich vacillated over several interview requests made through Caplin, their attorney. Geoff Edgers, Washington Post, "A jazz legend said he was in desperate need of money. His friends had questions.," 11 July 2019 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

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

21 Sep 2019

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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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