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1. An unhappy and worried mental state
   - disturbance, upset
    
2. (physics) a secondary influence on a system that causes it to deviate slightly
    
3. Activity that is a malfunction, intrusion, or interruption
   "the term 'distress' connotes some degree of perturbation and emotional upset"
   - disturbance
    
4. A disposition that is confused or nervous and upset
   - fluster
    
5. The act of causing disorder
   - disruption

Derived forms: perturbations

See also: perturb

Type of: activity, agitation, discomposure, disturbance, influence

Encyclopedia: Perturbation