1. The act of causing disorder
   "The student's disruption caused a perturbation in the classroom routine";
   - disruption
    
2. An unhappy and worried mental state
   "there was too much anger and perturbation";
   - disturbance, upset
    
3. A disposition that is confused or nervous and upset
   "The unexpected question caused a perturbation in the normally composed speaker";
   - fluster
    
4. (physics) a secondary influence on a system that causes it to deviate slightly
   "The gravitational perturbation of the moon affects Earth's tides"
    
5. Activity that is a malfunction, intrusion, or interruption
   "the term ‘distress’ connotes some degree of perturbation and emotional upset";
   - disturbance

Derived forms: perturbations

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

Encyclopedia: Perturbation