fluctuate

verb

fluc·​tu·​ate ˈflək-chə-ˌwāt 

-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

Synonyms

• change
• mutate
• shift
• snap
• vary

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 ultimate import of much of this work is that humans are themselves randomly fluctuating particles whose behavior, in aggregate, can be forecast by probabilistic methods. —Alex Ross, The New Yorker, 15 Apr. 2024

Due to these bottlenecks and fluctuating immigration patterns, the EB-5 program became less popular. —Kyle J. Russell, USA TODAY, 12 Apr. 2024

Relying this heavily on water sales is problematic, Reznik said, because water use can fluctuate greatly from year to year. —Ian James, Los Angeles Times, 10 Apr. 2024

The tally is expected to fluctuate as U.S. officials scramble to finalize key details on the project, including which humanitarian relief organizations and foreign governments are willing to help carry the shipments to shore and distribute them to ease the humanitarian crisis unfolding in Gaza. —Anne Flaherty, ABC News, 9 Apr. 2024

Full coverage around your toes will keep your feet cozy as the spring weather continues to fluctuate, and the reliable cork and latex footbed will still mold to your feet for a supremely personal fit. —Merrell Readman, Travel + Leisure, 6 Apr. 2024

Tamara Thomsen, a maritime archeologist with the Wisconsin Historical Society, tells the publication that the recent uptick is likely due to fluctuating water levels and greater public awareness of how to report discoveries. —Sarah Kuta, Smithsonian Magazine, 2 Apr. 2024

His income has fluctuated in that time, but 2023 was a good year for the Bidens, with an additional $40,462 in income, compared to 2022. —Chris Morris, Fortune, 16 Apr. 2024

While the company generated just over $4 million in revenue in 2023, Trump Media’s valuation has fluctuated wildly since going public in March, at one point reaching more than $7 billion. —William Turton, WIRED, 15 Apr. 2024

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

Kids Definition

fluctuate

verb

fluc·​tu·​ate ˈflək-chə-ˌwāt 

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

ˌflək-chə-ˈwā-shən 

noun