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

Examine search trends to see seasonal fluctuations and identify opportunities to adapt targeting. —Bahram Moshrefnoory, Forbes, 5 Nov. 2024

Manage these conditions by following your treatment plan to help prevent ferritin fluctuations. —Lindsay Curtis, Health, 5 Nov. 2024

Depression High added sugar intake can lead to fluctuations in blood sugar levels, resulting in mood swings, irritability, and fatigue, which may worsen feelings of depression. —Lauren Panoff, Mph, Rd, Verywell Health, 4 Nov. 2024

Several models freeze their results the night before Election Day, and most major pollsters have concluded their surveys, meaning there is unlikely to be any more fluctuation in these predictions. —David Faris, Newsweek, 4 Nov. 2024

Word History

First Known Use

15th century, in the meaning defined above

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