perturbation

Meanings

• an unhappy and worried mental state
• (physics) a secondary influence on a system that causes it to deviate slightly
• activity that is a malfunction, intrusion, or interruption
  • "the term `distress' connotes some degree of perturbation and emotional upset"
• a disposition that is confused or nervous and upset
• the act of causing disorder

Synonyms

disruption, disturbance, fluster, upset