- perturb (v.)
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- late 14c., from Old French perturber "disturb, confuse" (14c.) and directly from Latin perturbare "to confuse, disorder, disturb," especially of states of the mind, from per- "through" (see per) + turbare "disturb, confuse," from turba "turmoil, crowd" (see turbid). Related: Perturbed; perturbing.