perturb

verb per·turb \ pər-ˈtərb \

Definition of perturb

transitive verb

1 :to cause to be worried or upset :disquiet

2 :to throw into confusion :disorder

3 :to cause to experience a perturbation

—

perturbable

play \pər-ˈtər-bə-bəl\ adjective

See perturb defined for English-language learners

See perturb defined for kids

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 of perturb from the Web

Canadian and Mexican officials were initially perturbed by Trump’s threats, but more recently seemed to be giving little credence to them.

— don lee, chicagotribune.com, "Why Trump's threat to withdraw from NAFTA is an empty one," 30 Aug. 2017
The Champions League group stage draw on Thursday evening left some fans pleased and others (Spurs) perturbed as the balls were drawn in Monaco.

— SI.com, "VIDEO: Totti Can't Help But Laugh at Buffon After Handing Juventus Tough Draw in Champions League," 24 Aug. 2017
Interestingly, customers excited by the prospect of trying cricket nachos always seemed to be accompanied by those who perturbed by the idea.

— jordan c. axelson, Milwaukee Journal Sentinel, "Catch them while you can: Cricket nachos debut at Wisconsin State Fair," 9 Aug. 2017
Whether Trump knows enough to be perturbed by this sort of gamesmanship is an open question.

— jason zengerle, GQ, "What If Mike Pence Becomes President?," 8 Aug. 2017
That's what has left Trump increasingly perturbed with Sessions.

— joseph gerth, The Courier-Journal, "Mitch McConnell should stop Donald Trump from scuttling Russia investigation | Joseph Gerth," 28 July 2017
Fosse finally put his foot down with that one perturbing fan request.

— janie mccauley, chicagotribune.com, "For many major leaguers, the fan mail piles up for months," 5 July 2017
The (maybe) Giant and Señorita Dido, apparently perturbed by what looks like the birth of the evil spirit BOB, appear to send a figure of goodness and light to earth.

— vanityfair.com, "Twin Peaks: Trying to Make Sense of the Show’s Most Bonkers Episode," 26 June 2017
The (maybe) Giant and Señorita Dido, apparently perturbed by what looks like the birth of the evil spirit BOB, appear to send a figure of goodness and light to earth.

— joanna robinson, HWD, "Twin Peaks: Trying to Make Sense of the Show’s Most Bonkers Episode," 26 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'perturb.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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.

Origin and Etymology of perturb

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

NEW! Time Traveler

First Known Use: 14th century

See Words from the same year

perturb Synonyms

Synonyms

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

Antonyms

calm, compose, quiet, settle, soothe, tranquilize (also tranquillize)

Related Words

aggravate, anger, annoy, bug, chafe, chivy (or chivvy), exasperate, fret, gall, get, grate, harass, harry, irk, irritate, nettle, peeve, pester, pique, put off, put out, rile, vex; bedevil, haunt, plague; abash, confound, confuse, discomfit, disconcert, discountenance, embarrass, faze, fluster, jar, mortify, nonplus, rattle, shake up; daunt, demoralize, discourage, dishearten, dispirit, unnerve

Near Antonyms

allay, alleviate, assuage; appease, conciliate, mollify, pacify, placate, propitiate

Synonym Discussion of 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

PERTURB Defined for English Language Learners

perturb

verb

Definition of perturb for English Language Learners

: to cause (someone) to be worried or upset

PERTURB Defined for Kids

perturb

verb per·turb \ pər-ˈtərb \

Definition of perturb for Students

perturbed; perturbing

:to disturb in mind :trouble greatly

Word Root of perturb

The Latin word turba, meaning “disorder,” gives us the root turb. Words from the Latin turba have something to do with disorder. To disturb is to cause disorder to something or to someone's feelings. To perturb, or trouble, is to cause disorder to someone's mind. Anything turbulent is in a state of violence or disorder.