1325-75;Middle Englishperturben (< Old Frenchperturber) < Latinperturbāre to throw into confusion, equivalent to per-per- + turbāre to disturb; see turbid
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.