perturb in WordNet English dictionary

1. disturb in mind or make uneasy or cause to be worried or alarmed
   "She was rather perturbed by the news that her father was seriously ill"
   perturb  unhinge  disquiet  trouble  cark  distract  disorder 
   
2. throw into great confusion or disorder
   "Fundamental Islamicists threaten to perturb the social order in Algeria and Egypt"
   perturb  derange  throw out of kilter 
   
3. cause a celestial body to deviate from a theoretically regular orbital motion, especially as a result of interposed or extraordinary gravitational pull
   "The orbits of these stars were perturbed by the passings of a comet"
   perturb 
   
4. disturb or interfere with the usual path of an electron or atom
   "The electrons were perturbed by the passing ion"
   perturb