perturbation

noun

The act of perturbing.

noun

The state of being perturbed; agitation.

noun

A small change in a physical system, such as a variation in a planet’s orbit resulting from the gravitational influence of other celestial bodies.

noun

The act of perturbing, or the state of being perturbed; disturbance; disorder; especially, disquiet of mind; restlessness or want of tranquillity of mind; commotion of the passions.

noun

Variation; especially, irregular or violent variation.

noun

A cause of disquiet.

noun

In astronomy, a deviation of the motion of a planet or comet from a fixed orbit or from its regular velocity in that orbit.

noun

The act of perturbing, or the state of being perturbed; esp., agitation of mind.