fluctuation

American  

[fluhk-choo-ey-shuhn] / ˌflʌk tʃuˈeɪ ʃən /

noun

1. continual change from one point or condition to another.

2. wavelike motion; undulation.

3. Genetics. a body variation due to environmental factors and not inherited.

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fluctuation British  

/ ˌflʌktjʊˈeɪʃən /

noun

1. constant change; vacillation; instability

2. undulation

3. a variation in an animal or plant that is determined by environment rather than heredity

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Usage

What does fluctuation mean? Fluctuation is continual change. It’s a noun form of the verb fluctuate, meaning to continually change or shift back and forth. Fluctuation is most commonly used in the context of abstract or intangible things that frequently change, such as temperature, the stock market, or someone’s mood. Example: The fluctuation of the volume on my TV is really annoying—it gets louder during commercials and then it gets quiet again when the show comes back on.

Other Word Forms

• nonfluctuation noun

Etymology

Origin of fluctuation

1400–50; late Middle English < Latin fluctuātiōn- (stem of fluctuātiō ) a fluctuation, wavering. See fluctuate, -ion

Explanation

The noun fluctuation refers to the deviations along the path from one point to another. We see frequent fluctuations in the stock market, as prices go up or down, and also in the weather, which is always changing. The original form of the word fluctuation appeared as a mid-15th-century French word derived from the Latin fluctuationem, meaning "vacillation." The verb stem fluctuāre meant "to undulate," referring to waves, giving rise to the idea of change and movement that is at the heart of the word. It might help to remember that fluctuation has the same root as the word fluent, and to think of it as something flowing, with frequent change along the way.

Example Sentences

“The new-energy vehicles market has entered a phase of normal adjustment,” it added, saying that the short-term fluctuation was expected and does not reflect the market’s long-term trajectory.

From The Wall Street Journal • Feb. 12, 2026

This is up 13% on the last three months, but due to fluctuation over the last year represents a smaller increase - of 2% - from September 2024.

From BBC • Nov. 27, 2025

The additional energy used during measurement can provide richer information about the clock's behavior, not only counting ticks but capturing every minor fluctuation.

From Science Daily • Nov. 17, 2025

“I think there is going to be a short-term fluctuation in the trend that ultimately corrects itself and resumes the path it was on while Netanyahu is in power,” he said.

From Salon • Sep. 5, 2025

The computer reported no change in pressure over that time, other than a minor fluctuation based on temperature.

From "The Martian" by Andy Weir

Related Words

• variation