Perturbation or perturb may refer to any of numerous concepts in several fields: Perturbation theory, mathematical methods that give approximate solutions to problems that can't be solved exactly Perturbation (geology), changes in the nature of alluvial deposits over time Perturbation (astronomy), alterations to an object's orbit for example caused by gravitational interactions with other bodies Perturbation theory (quantum mechanics), a set of approximation schemes directly related to mathe… (More on Perturbation)