encumber

balk, check, constrain, curb, rein, restrain

bind, chain, halter, leash, tether, tie

arrest, brake, delay, retain, retard

barricade, block, blockade, roadblock

bog (down), mire

choke, smother, stifle, strangle, suffocate

baffle, foil, frustrate, stump, thwart

derail, disrupt, sabotage

muzzle, repress, suppress

confine, hedge (in), hem (in)

clog, clutter, fill, pack

heap, mound, pile, stack

press, weigh

strain, tax

overburden, overload, overtax, surcharge

hamper, handicap

afflict, oppress