When you're on an airplane with your friend who's terrified of flying, you'll be able to sense her perturbation, even if she doesn't say a word about how scared she is. The noun perturbation means "anxiety or uneasiness."

Perturbation means "a state of agitation," or it can refer to whatever's causing the anxiety. Your brother's weird haircut could be the perturbation that's upsetting your mom at Thanksgiving dinner. It usually means a personal feeling of upset or nervousness, but perturbation can also be a physical disruption of some kind, like a perturbation in a river that makes the water become choppy and dangerous. In astronomy, perturbation is a change caused by the gravitational pull of a celestial body.

Definitions of perturbation
  1. noun
    the act of causing disorder
    synonyms: disruption
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    breakdown, dislocation
    the act of disrupting an established order so it fails to continue
    surprisal, surprise
    the act of surprising someone
    type of:
    the act of disturbing something or someone; setting something in motion
  2. noun
    an unhappy and worried mental state
    synonyms: disturbance, upset
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    type of:
    a mental state of extreme emotional disturbance
  3. noun
    a disposition that is confused or nervous and upset
    synonyms: fluster
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    type of:
    a temperament that is perturbed and lacking in composure
  4. noun
    activity that is a malfunction, intrusion, or interruption
    “the term `distress' connotes some degree of perturbation and emotional upset”
    synonyms: disturbance
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    bother, fuss, hassle, trouble
    an angry disturbance
    magnetic storm
    a sudden disturbance of the earth's magnetic field; caused by emission of particles from the sun
    type of:
    any specific behavior
  5. noun
    (physics) a secondary influence on a system that causes it to deviate slightly
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    (astronomy) any perturbation of the mean motion or orbit of a planet or satellite (especially a perturbation of the earth's moon)
    (astronomy) a real or apparent slow oscillation of a moon or satellite
    type of:
    the effect of one thing (or person) on another
Word Family

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