verb per·turb \pər-ˈtərb\

Definition of perturb

  1. transitive verb
  2. 1 :  to cause to be worried or upset :  disquiet

  3. 2 :  to throw into confusion :  disorder

  4. 3 :  to cause to experience a perturbation


play \-ˈtər-bə-bəl\ adjective

Examples of perturb in a sentence

  1. It perturbed him that his son was thinking about leaving school.

  2. the caller's strange remark perturbed me enough to keep me awake that night

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

First Known Use: 14th century

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


verb per·turb \pər-ˈtərb\

Definition of perturb for English Language Learners

  • : to cause (someone) to be worried or upset

PERTURB Defined for Kids


verb per·turb \pər-ˈtərb\

Definition of perturb for Students




  1. :  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.

Seen and Heard

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capable of being understood in two ways

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