fluctuate
Americanverb (used without object)
-
fluctuates,
present (3rd person singular)
-
fluctuated,
past participle, past
-
fluctuating
present participle
-
to change continually; shift back and forth; vary irregularly.
The price of gold fluctuated wildly last month.
-
to move back and forth in waves.
- Synonyms:
- oscillate
verb (used with object)
-
fluctuates,
present (3rd person singular)
-
fluctuated,
past participle, past
-
fluctuating
present participle
verb
-
to change or cause to change position constantly; be or make unstable; waver or vary
-
(intr) to rise and fall like a wave; undulate
Usage
What does fluctuate mean? Fluctuate means to continually change or shift back and forth. The verb is most commonly used in the context of abstract or intangible things that frequently change, such as temperature, the stock market, or someone’s mood. This kind of continual change is called fluctuation. Example: The volume on my TV keeps fluctuating—it gets louder during commercials and then it gets quiet again when the show comes back on.
Synonym Usage
See waver 1.
Other Word Forms
Derived Forms
Inflected Forms
Participles
Conjugated Forms
Present
-
fluctuatesimple
-
fluctuatessimple
-
have fluctuatedperfect
-
has fluctuatedperfect
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am fluctuatingprogressive
-
are fluctuatingprogressive
-
is fluctuatingprogressive
-
have been fluctuatingperfect progressive
-
has been fluctuatingperfect progressive
Past
-
fluctuatedsimple
-
had fluctuatedperfect
-
was fluctuatingprogressive
-
were fluctuatingprogressive
-
had been fluctuatingperfect progressive
Future
Etymology
Origin of fluctuate
First recorded in 1625–35; from Latin fluctuātus “undulated,” past participle of fluctuāre “to flow,” equivalent to fluctu(s) “a flowing” (derivative of fluere “to flow”) + -ātus -ate 1
Explanation
Something that fluctuates varies or changes — it's the opposite of steady. Like the ups and downs of the stock market or the relationship status of a Hollywood starlet. Fluctuate is a verb that describes movement, sometimes irregular, but often rising and falling in a wave-like pattern. The tides fluctuate according to the weather and season, for example. Your emotions fluctuate depending on what happens throughout the day, and so does your weight. In fact, you usually weigh less in the morning, before you've eaten. You're also taller, since your spine compresses as you walk around. So your height fluctuates, too.
Vocabulary lists containing fluctuate
Tier 2 Words for the SBAC ELA Items
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List 3
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Darius the Great Is Not Okay
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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:
However, the photons in each type of light fluctuate and interact in different ways.
From Science Daily ● Aug. 8, 2026
Experts say camels comfortably beat the heat up to around 40C by mainly allowing their body temperature to fluctuate by several degrees throughout the day to deal with outside temperature.
From BBC ● Jul. 22, 2026
Giant defense contractors could benefit from DSRB-backed financing, say boosters, because government budgets often fluctuate annually, raising funding uncertainty that can increase borrowing costs.
From The Wall Street Journal ● Jul. 7, 2026
An expected inheritance can fluctuate for any number of reasons, and no one is entitled to it until it is actually distributed.
From MarketWatch ● Jul. 6, 2026
Rick said, “A humanoid robot is like any other machine; it can fluctuate between being a benefit and a hazard very rapidly. As a benefit it’s not our problem.”
From "Do Androids Dream of Electric Sheep?" by Philip K. Dick
As packages are unveiled and sold, available inventory on the website fluctuates — which means fans can spend a lot of time checking and rechecking.
From Los Angeles Times ● Aug. 20, 2026
It’s one of the largest concentrations of capybaras in São Paulo, though its exact number of members fluctuates.
From Slate ● May 27, 2026
The cost of that fluctuates more directly in response to the oil price, so the latest global uncertainty has pushed up bills for those households refilling their tanks.
From BBC ● May 5, 2026
The Nasdaq 100, consisting nearly 60% of technology stocks, fluctuates more sharply in price than older indexes such as the S&P 500 or the Dow Jones Industrial Average.
From The Wall Street Journal ● Mar. 13, 2026
In addition, receptivity to innovation fluctuates in time within the same region.
From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond
His salary has fluctuated with different jobs, and he has been a student, but the CMS has often struggled to keep up, he told us.
From BBC ● Aug. 17, 2026
The revenues of 1736 Family Crisis Center have fluctuated in recent years.
From Los Angeles Times ● Aug. 6, 2026
For most of the past decade that gap fluctuated between $10 and $15 a barrel.
From MarketWatch ● Jul. 21, 2026
Oil prices have fluctuated, but as of early July, the budgetary impact appears limited given the scale of Iranian attacks.
From The Wall Street Journal ● Jul. 16, 2026
I fluctuated between anticipation so intense that it was very nearly pain, and an insidious fear that picked at my resolve.
From "Twilight" by Stephenie Meyer
Taipei, Singapore, Jakarta and and Wellington were also up, with Manila fluctuating.
From Barron's ● Aug. 14, 2026
What the polls generally failed to foresee—and arguably shouldn’t have been expected to, given the fluctuating field—was that just enough voters would ultimately coalesce behind Crowley to put him over the top.
From Slate ● Aug. 12, 2026
These adaptations evolved to optimize energy storage and usage in environments with fluctuating food availability.
From Science Daily ● Aug. 4, 2026
But, mindful of fluctuating costs, they have also been taking steps to reduce their fuel consumption, while "squirreling away that extra little bit of cash".
From BBC ● Jul. 18, 2026
I was out of the water, if only by a fluctuating two, three feet.
From "Life of Pi" by Yann Martel
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.
