<p><strong>Verb (used with object):</strong></p><ul><li>to disturb or disquiet greatly in mind; agitate: I can see how such a massive change in your routine would perturb you.</li><li>to throw into great disorder: Huge construction projects can take years to finish, and meanwhile, can greatly perturb the neighborhood.</li><li>Astronomy: to cause perturbation in the orbit of (a celestial body).</li></ul>