Meaning of perturbation

Definition of perturbation

(noun) an unhappy and worried mental state; "there was too much anger and disturbance"; "she didn't realize the upset she caused me"
(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"; "he looked around for the source of the disturbance"; "there was a disturbance of neural function"
a disposition that is confused or nervous and upset
the act of causing disorder

Other information on perturbation

WIKIPEDIA results for perturbation
Amazon results for perturbation