perturbation

Noun

• the act of causing disorder

• a disposition that is confused or nervous and upset

• activity that is a malfunction, intrusion, or interruption
  • the term `distress' connotes some degree of perturbation and emotional upset
    
  • he looked around for the source of the disturbance
    
  • there was a disturbance of neural function
    

• (physics) a secondary influence on a system that causes it to deviate slightly

• an unhappy and worried mental state
  • there was too much anger and disturbance
    
  • she didn't realize the upset she caused me
    

Related words

• Synonyms: 
  disruption , fluster , disturbance , upset