fluctuation

noun

fluc·​tu·​a·​tion ˌflək-chə-ˈwā-shən How to pronounce fluctuation (audio)
-chü-ˈā-
plural fluctuations
Synonyms of fluctuationnext
: an act or instance of fluctuating : an irregular shifting back and forth or up and down in the level, strength, or value of something
Small fluctuations in prices are to be expected.
Some fluctuation in real estate values is not unusual.
North American species in general, having contended with blazing July days and frosty September nights as they evolved, are much more tolerant of temperature fluctuations than tropical species are.—Jonathan Franzen
fluctuational
ˌflək-chə-ˈwā-sh(ə-)nəl How to pronounce fluctuation (audio)
-chü-ˈā-
adjective

Synonyms of fluctuation

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Examples of fluctuation in a Sentence

political instability that resulted in wild fluctuations in the overseas stock markets
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Atmospheric fluctuations on shorter weekly or daily scales, such as sudden stratospheric warming events, polar vortex disruptions, or shifts in the Arctic Oscillation, can temporarily override the overarching El Niño pattern. — Ahmad Bajjey, CBS News, 16 Oct. 2026 Schimpf said the setup allows Anduril to give liquidity to employees without the distraction of stock price fluctuations. — Samantha Subin, CNBC, 15 Oct. 2026 These techniques made the steps more evenly distributed with fewer fluctuations between runs. — Muskanbhatia, Interesting Engineering, 13 Oct. 2026 But if the fear of small fluctuations in your blood sugar is still weighing on you, that’s okay. — Sukhman Rekhi, Verywell Health, 13 Oct. 2026 See All Example Sentences for fluctuation

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of fluctuation was in the 15th century

Rhymes for fluctuation

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Browse Nearby Words

fluctuatingly
fluctuation
fluctuational
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Cite this Entry

“Fluctuation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluctuation. Accessed 20 Oct. 2026.

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Medical Definition

fluctuation

noun
fluc·​tu·​a·​tion ˌflək-chə-ˈwā-shən How to pronounce fluctuation (audio)
1
: a motion like that of waves
especially : the wavelike motion of a fluid collected in a natural or artificial cavity of the body observed by palpation or percussion
2
a
: a slight and nonheritable variation
especially : such a variation occurring in response to environmental factors
b
: recurrent and often more or less cyclic alteration (as of form, size, or color of a bodily part)
fluctuate
ˈflək-chə-ˌwāt How to pronounce fluctuation (audio)
verb
fluctuated; fluctuating
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