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.
Sleep, diet and other factors can cause regular fluctuations for men. — Kathleen Felton, Washington Post, 1 Aug. 2026 Their strength has always been their ability to think beyond election cycles, market fluctuations, technological fads, and the crises of the moment. — David Rosowsky, Forbes.com, 1 Aug. 2026 Adapted from Blake’s poem into song by Hubert Parry, ‘Jerusalem’ may be slower-paced than ‘God Save The King’ but its fluctuations in pace and tone at least give it some momentum. — George Edwards, New York Times, 31 July 2026 But when stress, pollution, hormonal fluctuations, heat styling, and everyday life leave hair brittle, dull, and prone to breakage, there’s only so much a topical treatment can do. — Alessandra Signorelli, Vogue, 27 July 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 5 Aug. 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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