perturb

verb

per·​turb pər-ˈtərb 

perturbed; perturbing; perturbs

transitive verb

1

: 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

2

: to throw into confusion : disorder

perturbing the social order

3

: 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

pər-ˈtər-bə-bəl 

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.

Synonyms

• agitate
• ail
• alarm
• alarum
• bother
• concern
• derail
• discomfort
• discompose
• dismay
• disquiet
• distemper
• distract
• distress
• disturb
• exercise
• flurry
• frazzle
• freak (out)
• fuss
• hagride
• undo
• unhinge
• unsettle
• upset
• weird out
• worry

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

Trump's push for peace -- which has been twinned with fierce public criticism of Ukraine and President Volodymyr Zelenskyy -- has been welcomed by America's allies, though leaders have been perturbed by the president's apparent alignment with Russia's false narratives about the conflict. —David Brennan, ABC News, 13 Mar. 2025

The camera showed Jewels looking perturbed in the audience, but Suzie tells EW why Jewels didn't immediately jump to out Arrietty's actions. —EW.com, 9 Mar. 2025

Hernandez contends in his lawsuit that he was pushed out of his job of nearly a decade in August 2022 because Platt had become increasingly perturbed when Hernandez would challenge the statistics Platt would cite in public statements about city accomplishments. —Mike Hendricks, Kansas City Star, 28 Feb. 2025

Some in the industry were perturbed that the White House is apparently looking to include more volatile currencies among the holdings. —Miles Klee, Rolling Stone, 3 Mar. 2025

Word History

Etymology

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

Rhymes for perturb

• disturb
• reverb
• superb
• blurb
• curb
• erb
• herb
• kerb
• serb
• verb

Kids Definition

perturb

verb

per·​turb pər-ˈtərb 

: to disturb greatly especially in mind

perturbable

-ˈtər-bə-bəl 

adjective