fluc·tu·ate | \ˈflək-chə-ˌwāt, -chü-ˌāt\
fluctuated; fluctuating

Definition of fluctuate 

intransitive verb

1 : to shift back and forth uncertainly Oil prices fluctuated. Temperatures fluctuated.

2 : to rise and fall in or as if in waves The boat fluctuated on the rough sea.

transitive verb

: to cause to fluctuate

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Other Words from fluctuate

fluctuation \ˌflək-chə-ˈwā-shən, -chü-ˈā- \ noun
fluctuational \ˌflək-chə-ˈwā-shnəl, -shə-nᵊl, -chü-ˈā- \ adjective

Synonyms & Antonyms for fluctuate


change, mutate, shift, snap, vary


plateau, stabilize

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Choose the Right Synonym for fluctuate

swing, sway, oscillate, vibrate, fluctuate, waver, undulate mean to move from one direction to its opposite. swing implies a movement of something attached at one end or one side. the door suddenly swung open sway implies a slow swinging or teetering movement. trees swaying in the breeze oscillate stresses a usually regular alternation of direction. an oscillating fan vibrate suggests the rapid oscillation of an elastic body under stress or impact. the vibrating strings of a piano fluctuate suggests constant irregular changes of level, intensity, or value. fluctuating interest rates waver stresses irregular motion suggestive of reeling or tottering. the exhausted runner wavered before collapsing undulate suggests a gentle wavelike motion. an undulating sea of grass

Examples of fluctuate in a Sentence

His popularity has fluctuated during his term in office. In the desert, the temperature fluctuates dramatically.

Recent Examples on the Web

The game continued to fluctuate wildly from end to end. Tariq Panja, New York Times, "World Cup 2018: Belgium Shocks Japan With Stunning Rally," 4 July 2018 Excluding auto sales, which tend to fluctuate significantly month to month, retail spending grew 0.9%. Eric Morath, WSJ, "U.S. Retail Sales Soared in May," 14 June 2018 Temperatures are forecast to fluctuate from the upper 70s to the upper 80s during the weekend and into early next week, according to the National Weather Service. Eder Campuzano, OregonLive.com, "Portland Saturday weather: Clear skies and highs nearing 80 (once the clouds go away)," 12 May 2018 Hosmer seemed to genuinely fluctuate between being perturbed and bemused before Wednesday’s game against the Nationals. Kevin Acee, sandiegouniontribune.com, "Eric Hosmer shocked by supposed rift with Andy Green, hint of Padres discord," 9 May 2018 The astronomers' insight is that a rotating, mountainous planet presents a changing silhouette during transit, causing measurements of the dip in light to fluctuate. Bob Henderson, Scientific American, "Exoplanet Everests May Be Detectable When Giant Telescopes Come Online," 1 May 2018 Patcsche is now in the process of pricing her soybeans to be harvested later this year and in 2019—but prices continue to fluctuate in part due to trade war fears. Lucinda Shen, Fortune, "How Trump's Tariffs Are Squeezing His Farmer Support Base," 18 Apr. 2018 Moreover, the likelihood of victims receiving timely attention is shown to fluctuate based on economic status and race, a pattern also seen in the way those reporting rapes are questioned by police and treated in court. Brian Lowry, CNN, "'I Am Evidence' examines problem of untested rape kits," 16 Apr. 2018 The number of American directors and Hollywood stars tends to fluctuate at Cannes from year to year. Justin Chang, latimes.com, "Spike Lee and David Robert Mitchell films will compete in the most surprising Cannes lineup in years," 12 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fluctuate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fluctuate

1604, in the meaning defined at intransitive sense 2

History and Etymology for fluctuate

Latin fluctuatus, past participle of fluctuare, from fluctus flow, wave, from fluere — more at fluid

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Statistics for fluctuate

Last Updated

19 Oct 2018

Look-up Popularity

Time Traveler for fluctuate

The first known use of fluctuate was in 1604

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More Definitions for fluctuate



English Language Learners Definition of fluctuate

: to change level, strength, or value frequently


fluc·tu·ate | \ˈflək-chə-ˌwāt \
fluctuated; fluctuating

Kids Definition of fluctuate

: to change continually and especially up and down The temperature fluctuated.

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Comments on fluctuate

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