vacillate
Americanverb (used without object)
-
vacillates,
present (3rd person singular)
-
vacillated,
past participle, past
-
vacillating
present participle
verb
-
to fluctuate in one's opinions; be indecisive
-
to sway from side to side physically; totter or waver
Synonym Usage
See waver 1.
Other Word Forms
Derived Forms
Inflected Forms
Participles
Conjugated Forms
Present
-
vacillatesimple
-
vacillatessimple
-
have vacillatedperfect
-
has vacillatedperfect
-
am vacillatingprogressive
-
are vacillatingprogressive
-
is vacillatingprogressive
-
have been vacillatingperfect progressive
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has been vacillatingperfect progressive
Past
-
vacillatedsimple
-
had vacillatedperfect
-
was vacillatingprogressive
-
were vacillatingprogressive
-
had been vacillatingperfect progressive
Future
Etymology
Origin of vacillate
First recorded in 1590–1600; from Latin vacillātus (past participle of vacillāre “to sway to and fro”); see -ate 1
Explanation
Vacillate means to waver back and forth, unable to decide. You might vacillate between ordering waffles and pancakes at your favorite diner — it’s hard to pick just one when both are so tasty! Something that vacillates sways or fluctuates, often quite unsteadily. So use this verb to describe the staggering motions of a person who has had too much to drink, as well as the opinions of someone who can’t make up her mind. Synonyms include vibrate, hesitate, and waver. A wise Ethiopian proverb advises, "Do not vacillate or you will be left in between doing something, having something, and being nothing.”
Vocabulary lists containing vacillate
Grade 12, List 5
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100 SAT Words Beginning with "V"
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Long Walk to Freedom
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
A towering outside hitter, he was known for his ability to vacillate between power and finesse.
From Los Angeles Times ● Aug. 28, 2025
The Oscars can often vacillate between insidery navel-gazing and a ho-hum march toward best picture, but occasionally an acceptance speech cuts through the noise with authenticity.
From New York Times ● Mar. 13, 2023
His leadership skills were lackluster, he was not a charismatic or inspiring speaker, he tended to vacillate in decision-making and he struggled to retain the best staffers.
From Salon ● Jul. 24, 2022
We are a nation traumatized into forgetting, psyches so pulverized by mass death that we vacillate wildly between rage and numbness—waiting until the cycle begins again, so frequent it masquerades as normalcy.
From Slate ● May 25, 2022
His yellow eyes vacillate between me and Autumn.
From "Kwame Crashes the Underworld" by Craig Kofi Farmer
It is closer to music than epic, a mesmerizing suite of songs that conveys Tennyson’s private sorrow as he vacillates from unbearable agony to precarious hope.
From The Wall Street Journal ● Feb. 20, 2026
Peake’s staid and knowing portrayal stands in contrast and complement to that of Petticrew, whose resolute manner vacillates between a flinty swagger and true anguish.
From Salon ● Nov. 14, 2024
As the score vacillates between rhythmic, melodic passages and warped dissonance, they look at times like they’re trying to worm their way out of their bodies.
From New York Times ● Apr. 24, 2023
But it wouldn’t be a reach to believe the NBA legend’s criticism of his portrayal in the show — as a tempestuous and profane malcontent who vacillates between anger and despair — helped boost ratings.
From Washington Post ● May 15, 2022
The conflict of diametrically opposing forces shows itself plainly in his attitude which vacillates between the stiffest formality and the easiest assurance.
From Poise: How to Attain It by D. Starke
Both sides have vacillated between tough talk and de-escalation in recent days, but the rhetoric took a harder turn on Tuesday.
From The Wall Street Journal ● Oct. 15, 2025
His children, Kelly and Jack, vacillated between showering him with affection and berating him for not catering to their whims.
From Salon ● Jul. 24, 2025
It was the first in a series of scary scenes for Brinkley, whose feelings for Joel vacillated between veneration, unconditional love and abject fear.
From Los Angeles Times ● Apr. 29, 2025
Her parents vacillated between wanting to take a hard line and accommodating Olivia’s apparent limitations for the sake of ease.
From Slate ● Jan. 4, 2025
She and Bunny had a relationship the likes of which I had seldom seen except in couples married for twenty years or more, a relationship which vacillated between the touching and the annoying.
From "The Secret History" by Donna Tartt
The film has wavered too much, and the story’s vacillating opinion on devices starts to point back at Disney.
From Salon ● Jun. 21, 2026
They pose the theory that the stock market is vacillating between thematic momentum and macro conditions.
From MarketWatch ● Jun. 15, 2026
Oppenheimer modulates the lighting during the scenes from cool to warm and back again, underlining the vacillating feelings they can’t acknowledge outright.
From New York Times ● Dec. 5, 2024
We hate vacillating on matters of major consequence.
From Seattle Times ● Jan. 14, 2024
Three overlapping reasons appear to have converged in Adams’s mind and provided decisive direction to a foreign policy that, until then, had been vacillating between the incompatible agendas of the Federalists and the Republicans.
From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
