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
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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 studio spectators cut him off with a loud, extended chorus of boos, as Colbert appeared to vacillate between laughing and choking up.
From Slate ● Jul. 18, 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
Because of this, he began to seek out new allies and to vacillate with France during the campaign the French undertook in the Kingdom of Naples against the Spaniards besieging Gaeta.
From "The Prince" by Niccolò Machiavelli
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
When the conspiracy at the center of “The Chair Company” consumes the life of Ron Trosper, he vacillates between screaming fury and the type of validation that lights up his smile from the inside.
From Salon ● Oct. 13, 2025
Meanwhile, Merritt vacillates between despair at the prospect of her eviction and elation when she dreams of returning to Poplar Boulevard.
From Los Angeles Times ● Jun. 3, 2024
“He vacillates between being very intense and focused about his work and just really silly and fun,” Diarra Kilpatrick, who plays Paul’s wife, Clara, said in a video interview.
From New York Times ● Mar. 2, 2023
But knowledge is changeable, and often vacillates between truth and error, yet, as a rule, is rectified more and more in the course of life, though certainly in very different degrees.
From The World As Will And Idea (Vol. 1 of 3) by Arthur Schopenhauer
In the 2000s, the company vacillated between a fashion-forward and a basics-focused approach—neither of which helped sales much.
From The Wall Street Journal ● Aug. 23, 2026
Instead, I vacillated between forgetting all about cancer some days and feeling like death was imminent others, and it was hard to predict what would prompt either extreme.
From Slate ● May 6, 2026
“He was begging to be able to do something on the offensive side,” Skipper said of the redshirt junior, who has vacillated between the offensive and defensive lines during his seven seasons with the team.
From Los Angeles Times ● Oct. 13, 2025
My emotions vacillated from fury to giddiness to crushing depression on an hourly basis.
From Salon ● Nov. 5, 2023
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
They pose the theory that the stock market is vacillating between thematic momentum and macro conditions.
From MarketWatch ● Jun. 15, 2026
The arrival of the Iamaleava brothers prompted quarterbacks Joey Aguilar and Robert McDaniel to enter the transfer portal, with Demaricus Davis vacillating on his future, according to Foster.
From Los Angeles Times ● Apr. 27, 2025
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 are a country, and a world, chasing its tail – vacillating between hatred, anger and a desire for peace.
From Salon ● Sep. 19, 2024
“Why, what do you make out that they done with their buttons then, Jack?” asked the landlord, vacillating weakly.
From "Great Expectations" by Charles Dickens
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.
