Same word as obstruct:

arrest, bar, barricade, block, check, choke, clog, close, congest, crab, curb, cut off, drag one's feet, fill, foul up, frustrate, get in the way, hamper, hamstring, hang up, hide, hinder, hold up, impede, inhibit, interfere, interrupt, mask, monkey with, obscure, occlude, plug, restrain, retard, sandbag, shield, shut off, slow down, stall, stonewall, stop, stopper, stymie, terminate, throttle, thwart, trammel, weigh down