perturb

verb

1. 1

   throw into great confusion or disorder

   Fundamental Islamicists threaten to perturb the social order in Algeria and Egypt

2. 2

   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

3. 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

4. 4

   disturb or interfere with the usual path of an electron or atom

   The electrons were perturbed by the passing ion