fluctuate

verb

fluc·​tu·​ate ˈflək-chə-ˌwāt How to pronounce fluctuate (audio)
-chü-ˌāt
fluctuated; fluctuating

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
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
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.
The Journey Of A Thousand Miles Began With A Natural Raft Approximately 30 to 40 million years ago, South America was an isolated landmass, separated from Africa by an expanse of ocean that spanned 900 to 1,300 miles (1,800 km), depending on fluctuating sea levels. Scott Travers, Forbes, 11 Jan. 2025 Wind and other factors can sometimes cause spotfires to jump these lines, which is why containment percentages can fluctuate, the Fire Chiefs Association’s website added. Janhvi Bhojwani, NBC News, 10 Jan. 2025 Adding more natural gas to its portfolio would, however, expose Constellation to more risk related to fluctuating commodity prices, Enverus said. Rebecca F. Elliott, New York Times, 10 Jan. 2025 These metrics can fluctuate pretty wildly as teams go on shooting benders and goalies make (or don’t make) saves. James Mirtle, The Athletic, 9 Jan. 2025 See all Example Sentences for fluctuate 

Word History

Etymology

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

First Known Use

1604, in the meaning defined at intransitive sense 2

Time Traveler
The first known use of fluctuate was in 1604

Dictionary Entries Near fluctuate

Cite this Entry

“Fluctuate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluctuate. Accessed 20 Jan. 2025.

Kids Definition

fluctuate

verb
fluc·​tu·​ate ˈflək-chə-ˌwāt How to pronounce fluctuate (audio)
fluctuated; fluctuating
1
: to move up and down or back and forth like a wave
2
: to be constantly changing especially up and down
fluctuation noun

More from Merriam-Webster on fluctuate

Last Updated: - Updated example sentences
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