fluc·​tu·​ate | \ ˈflək-chə-ˌwāt How to pronounce fluctuate (audio) , -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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Synonyms & Antonyms for fluctuate



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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 Under a current proposal, the standard reservation window across all state parks would change, allowing flexibility for individual campgrounds to fluctuate between same-day registration up to 18 months in advance. oregonlive, "Oregon State Parks will open campground reservation window to 60 days," 12 Jan. 2021 Experts expect numbers to fluctuate over the next few days because of the holiday. Chronicle Staff, SFChronicle.com, "Coronavirus news from the Bay Area: Nov. 27-Dec. 3," 4 Dec. 2020 In response, Linux kernel developers introduced a change that causes the rate limit to randomly fluctuate between 500 and 2,000 per second. Dan Goodin, Ars Technica, "DNS cache poisoning, the Internet attack from 2008, is back from the dead," 12 Nov. 2020 Numbers fluctuate, but roughly 42 percent of the district’s 33,000 students — or about 14,000 students — are now attending virtually. Sarah Bahari, Dallas News, "To boost attendance and support struggling students, Irving ISD tries something new," 27 Jan. 2021 The numbers can fluctuate dramatically after holidays and weekends, and the figure is subject to revision. Star Tribune, "US registering highest deaths yet from the coronavirus," 7 Jan. 2021 Also, around the holidays, the numbers may fluctuate based on when people choose to get tested and when labs can process the results. Joe Mahr, chicagotribune.com, "Did Illinois see a post-Thanksgiving surge in COVID-19? The latest data offers a mixed picture.," 15 Dec. 2020 Bacteria levels can fluctuate rapidly based on any number of factors, including rainfall, but the harbor’s 2019 scores lagged behind those of 2018. Christine Condon, baltimoresun.com, "Baltimore’s Waterfront Partnership releases new vision for Inner Harbor swimming," 23 Sep. 2020 Hospitals throughout the state are at or near capacity, though the number of available beds can fluctuate by the hour, and so far few have had to transfer relatively few patients to the hospital. Guy Boulton, Milwaukee Journal Sentinel, "What's happening with the field hospital at State Fair Park? Here's an update.," 26 Nov. 2020

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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Time Traveler for fluctuate

Time Traveler

The first known use of fluctuate was in 1604

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Statistics for fluctuate

Last Updated

21 Feb 2021

Cite this Entry

“Fluctuate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluctuate. Accessed 3 Mar. 2021.

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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 How to pronounce fluctuate (audio) \
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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