fluctuation

noun

fluc·​tu·​a·​tion ˌflək-chə-ˈwā-shən 

-chü-ˈā-

plural fluctuations

: an act or instance of fluctuating : an irregular shifting back and forth or up and down in the level, strength, or value of something

Small fluctuations in prices are to be expected.

Some fluctuation in real estate values is not unusual.

North American species in general, having contended with blazing July days and frosty September nights as they evolved, are much more tolerant of temperature fluctuations than tropical species are.

—Jonathan Franzen

fluctuational

ˌflək-chə-ˈwā-sh(ə-)nəl 

-chü-ˈā-

adjective

Synonyms

• change
• flux
• inconstancy
• oscillation

Examples of fluctuation in a Sentence

political instability that resulted in wild fluctuations in the overseas stock markets

Recent Examples on the Web

X-ray radiation levels in the chamber were similar to those on the surface of Mars when there is strong solar activity, though solar flares and fluctuations in solar wind make actual Martian levels unpredictable. —Elizabeth Rayne, ArsTechnica, 19 Apr. 2025

Vulcan remains steadfast in its commitment to inherent value, patiently awaiting a price that aligns with its corporate quality, without succumbing to fads or market fluctuations. —Jim Osman, Forbes.com, 15 Apr. 2025

House Minority Leader Hakeem Jeffries (D-N.Y.) on Monday backed a stock trading ban for sitting members of Congress, after ripping Rep. Marjorie Taylor Greene (R-Ga.) for reportedly profiting off market fluctuations during President Trump’s tariff roller-coaster. —Tara Suter, The Hill, 15 Apr. 2025

The sale is a striking reminder of just how competitive—and resilient—the downtown Manhattan real estate market remains, even amid broader market fluctuations. —Abby Montanez, Robb Report, 15 Apr. 2025

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for fluctuation

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Medical Definition

fluctuation

noun

fluc·​tu·​a·​tion ˌflək-chə-ˈwā-shən 

1

: a motion like that of waves

especially : the wavelike motion of a fluid collected in a natural or artificial cavity of the body observed by palpation or percussion

2

a

: a slight and nonheritable variation

especially : such a variation occurring in response to environmental factors

b

: recurrent and often more or less cyclic alteration (as of form, size, or color of a bodily part)

fluctuate

ˈflək-chə-ˌwāt 

verb

fluctuated; fluctuating