fluctuate
- 01 B2 Upper Intermediate
to change often, especially by rising and falling in amount or level.
to shift back and forth or up and down in an irregular manner; frequently used in economic and scientific contexts.
Simple“The price of petrol tends to fluctuate based on the cost of oil.”
In context“Stock market indices continued to fluctuate throughout the fiscal quarter, driven by investor uncertainty regarding interest rate adjustments.”
- 02 C1 Advanced
to keep changing your mind or your feelings about something.
to be irresolute or to waver between different opinions or courses of action.
Simple“His mood seemed to fluctuate between excitement and deep worry.”
In context“Public opinion began to fluctuate as conflicting reports about the policy's impact reached the mainstream media.”
“It hopes plug-in solar panels will help households save money and reduce reliance on overseas fuel sources, the price of which has fluctuated in recent months due to the Middle East conflict.”
“All of these measures work to prevent the temperature fluctuating inside the house - in winter and summer - so much less energy is used.”
First attested in the 1630'; borrowed from Latin flūctuātus, perfect passive participle of flūctuō (“(of the sea) to surge, swell; (of man) to waver, fluctuate”), see -ate (verb-forming suffix) and -ate (adjective-forming suffix).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.