prevent

[1]

anticipate , forestall , foreclose , preclude , obviate , preclude , forbid , forestall , avert , avoid , prohibit , ban , bar , forbid , interdict , taboo , enjoin , proscribe , foil , frustrate , obstruct , debar , intercept , nip in the bud , abort , thwart , check , block , ward/fend/stave off , baffle , balk/baulk , (put a) stop (to) , arrest , (bring to a) halt , hinder , impede , curb , restrain , hamper , inhibit , delay , retard , slow , mitigate , control

[2]

keep