DISCONCERT

v. 25B6; verb UNSETTLE, nonplus, discomfit, throw/catch off balance, take aback, rattle, set someone back on their heels, unnerve, disorient, perturb, disturb, perplex, confuse, bewilder, baffle, fluster, ruffle, shake, upset, agitate, worry, dismay, discountenance; surprise, take by surprise, startle, put someone off (their stroke/stride), distract; informal throw, faze; N. Amer. informal discombobulate.