perturbation

per.tur.ba.tion

-noun

1. the act of perturbing

2. the state of being perturbed.

3. mental disquiet, disturbance, or agitation.

4. astronomy. deviation of a celestial body from a regular orbit about its primary, cause by the presence of one or more other bodies that act upon the celestial body.

World English Dictionary

5. physics. a secondary influence on a system that modifies simple behavior, such as the effect of the other electrons on one electron in an atom.

6. astronomy. a small continuous deviation in the inclination and eccentricity of the orbit of a planet or comet, due to the attraction of neighboring planets.

Science Dictionary

7. a small change in a physical system, most often in a physical system at equilibrium that is disturbed from the outside.

8. variation in a designated orbit, as of a planet, that results from the influence one or more external bodies. Gravitational attraction between planets can cause perturbations and cause a planet to deviate from its expected orbit. Perturbations in the orbit of stars have led to the discovery of planetary systems outside our solar system.

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