PERTURB is validvalid

to disturb greatly [v PERTURBED, PERTURBING, PERTURBS] : PERTURBABLE [adj], PERTURBATION [n], PERTURBER [n], PERTURBINGLY [adv]

47,676 of 196,601 in NWL2023·also valid in CSW24

to disturb greatly [v -ED, -ING, -S]