vacillate
Americanverb
-
to fluctuate in one's opinions; be indecisive
-
to sway from side to side physically; totter or waver
Related Words
See waver 1.
Other Word Forms
- vacillation noun
- vacillator noun
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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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.
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
You have to see it so many times because you have to vacillate between watching the show and watching the audience.
From Los Angeles Times • Oct. 13, 2024
But Mr. Putin seemed to vacillate on his own support for Mr. Prigozhin.
From New York Times • Jun. 24, 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
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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.