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 Secondary market bond prices fluctuated from the high 90s down to the high 80s in early 2019. Erik Sherman, Fortune, "The Pain From WeWork’s Failed IPO Deepens as Bondholders Get Stuck Underwater," 12 Nov. 2019 Pain that comes and goes It’s also not unusual for the pain to come in waves or fluctuate in intensity, according to the Mayo Clinic. Carolyn L. Todd, SELF, "7 Signs & Symptoms of Kidney Stones You Need to Know," 12 Nov. 2019 The number of ballots counted daily during the last mayoral race in June fluctuated, but the Elections Department was able to count more than 20,000 ballots on some days. Dominic Fracassa, SFChronicle.com, "Nail-biter San Francisco races hinge on 70,000 uncounted ballots," 6 Nov. 2019 But the actual level of immigration fluctuated greatly. Richard Breitman, Time, "The Troubling History of How America's 'Public Charge' Immigration Rule Blocked Jews Fleeing Nazi Germany," 29 Oct. 2019 The turnover rate for employees with less than one year of service fluctuates between 25% and 28%. Stephanie Innes, azcentral, "Valleywise Health CEO to get an $85K pay raise despite objections by 2 board members," 23 Oct. 2019 Border Patrol custody fluctuates its facilities only hold migrants until they are processed and either released or sent to ICE custody. Colleen Long, chicagotribune.com, "Trump administration takes step to collect DNA samples from asylum-seekers," 21 Oct. 2019 Border Patrol custody fluctuates its facilities only hold migrants until they are processed and either released or sent to ICE custody. San Diego Union-Tribune, "US takes step to require DNA samples from asylum-seekers," 21 Oct. 2019 Her husband, also 63, is self-employed, and his income fluctuates. Los Angeles Times, "No health insurance? California will help, but you’ll pay if you’re not covered," 16 Oct. 2019

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

16 Nov 2019

Cite this Entry

“Fluctuate.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/fluctuates. Accessed 21 November 2019.

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More Definitions for fluctuate


How to pronounce fluctuate (audio)

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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