fluctuates

Fluctuates is the third-person singular present tense of the verb fluctuate. It describes a process in which something rises and falls or varies irregularly within a range. In general usage, to fluctuate means to move back and forth between different levels, rather than following a steady trend. The noun form fluctuation refers to the irregular variation itself.

The word derives from Latin fluctus (wave) and fluctuare (to wave, to rise and fall), reflecting the sense of oscillation. English adopted the term in the early modern period, and it is commonly used across scientific, economic, and everyday language.

Common contexts include economics and finance (prices fluctuate), meteorology (temperatures fluctuate), physiology (hormone levels fluctuate), and ecology (population sizes fluctuate). Fluctuations can differ in amplitude and frequency; statistical measures such as range or standard deviation describe their extent, while volatility refers to rapid or large fluctuations in markets. For example, stock prices fluctuate throughout a trading day, and monthly temperatures may fluctuate with the seasons. Understanding fluctuation helps in modeling systems that do not follow a simple, steady trajectory.