per·​turb pər-ˈtərb How to pronounce perturb (audio)
perturbed; perturbing; perturbs

transitive verb

: to cause to be worried or upset : disquiet, unsettle
Half way down the next flight, she smiled to think that a char-woman's stare should so perturb her.Edith Wharton
The crowd didn't seem to perturb them in the slightest …Nick Hornby
: to throw into confusion : disorder
perturbing the social order
: to cause to experience a perturbation see perturbation sense 2
Newton finally realized that the planetary orbits would be only approximate ellipses, for the mutual attractions of the planets would perturb their paths.Owen Gingerich
perturbable adjective

Did you know?

With its per- prefix, perturb meant originally "thoroughly upset", though today the word has lost most of its intense edge. Perturb and perturbation are often used by scientists, usually when speaking of a change in their data indicating that something has affected some normal process. When someone is referred to as imperturbable, it means he or she manages to remain calm through the most trying experiences.

Choose the Right Synonym for perturb

discompose, disquiet, disturb, perturb, agitate, upset, fluster mean to destroy capacity for collected thought or decisive action.

discompose implies some degree of loss of self-control or self-confidence especially through emotional stress.

discomposed by the loss of his beloved wife

disquiet suggests loss of sense of security or peace of mind.

the disquieting news of factories closing

disturb implies interference with one's mental processes caused by worry, perplexity, or interruption.

the discrepancy in accounts disturbed me

perturb implies deep disturbance of mind and emotions.

perturbed by her husband's strange behavior

agitate suggests obvious external signs of nervous or emotional excitement.

in his agitated state we could see he was unable to work

upset implies the disturbance of normal or habitual functioning by disappointment, distress, or grief.

the family's constant bickering upsets the youngest child

fluster suggests bewildered agitation.

his declaration of love completely flustered her

Examples of perturb in a Sentence

It perturbed him that his son was thinking about leaving school. the caller's strange remark perturbed me enough to keep me awake that night
Recent Examples on the Web Victim perturbed In my opinion, offenders like Bassett are the very worst in our society. Bea L. Hines, Miami Herald, 31 May 2024 Victim perturbed Under the agreement, negotiated by Bassett’s defense team and approved by the Miami-Dade State Attorney’s Office, Bassett is ordered to complete 10 years’ probation, is barred from unsupervised contact with minors and must stay away from the victim. Grethel Aguila, Miami Herald, 28 May 2024 Yet at the moment, the stock market isn’t perturbed by his apparent political strength, which is manifest in an array of public opinion polls showing a race with razor-thin margins — but with Mr. Trump, more often than not, in the lead. Jeff Sommer, New York Times, 12 Apr. 2024 Clearly they were perturbed by what was happening, and the oddest was the Galapagos Turtles, which are huge. Dana Taylor, USA TODAY, 29 Mar. 2024 As the grandson of four immigrants who landed on Ellis Island, David has become particularly perturbed by debate in the U.S. around immigration. Ryan Hogg, Fortune Europe, 20 Mar. 2024 He was more perturbed by the omission of Sabonis, who leads the NBA in rebounding, double-doubles and triple-doubles. Jason Anderson, Sacramento Bee, 16 Feb. 2024 This led to a deluge of good Twitter jokes and memes about the former President of the United States fielding a very stern, perturbed phone call from one of the film’s producers — Oprah. Jon Blistein, Rolling Stone, 29 Dec. 2023 Jacobs noted she was particularly perturbed by the effusive reaction to the film online., 23 Oct. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'perturb.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Middle English, from Middle French perturber, from Latin perturbare to throw into confusion, from per- + turbare to disturb — more at turbid

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of perturb was in the 14th century

Dictionary Entries Near perturb

Cite this Entry

“Perturb.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2024.

Kids Definition


per·​turb pər-ˈtərb How to pronounce perturb (audio)
: to disturb greatly especially in mind
perturbable adjective

More from Merriam-Webster on perturb

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