perturbation

英 [,pɜːtə'beɪʃ(ə)n] 美[,pɝtɚ'beʃən]

• n. [数][天] 摄动；不安；扰乱

1. an unhappy and worried mental state;

"there was too much anger and disturbance"

"she didn't realize the upset she caused me"

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

3. activity that is an intrusion or interruption;

"he looked around for the source of the disturbance"

"there was a disturbance of neural function"

4. a disposition that is confused or nervous and upset

5. the act of causing disorder