verb per·turb \ pər-ˈtərb \
|Updated on: 17 Jun 2018

Definition of perturb

1 : to cause to be worried or upset : disquiet
2 : to throw into confusion : disorder
3 : to cause to experience a perturbation


play \pər-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

Recent Examples of perturb from the Web

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

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


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

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.

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