| plug(verb, stop, close, end, check) |
| police(verb, defend) |
| portcullis |
| prohibit(verb, check, hinder, frustrate, thwart) |
| protect(verb, defend) |
| railing(noun, block, bar, hindrance, obstruction) |
| redoubt(noun, cover, position, guard, shield) |
| resistance(noun, cover, position, guard, shield) |
| sandbag(verb, check, block, obscure, hinder) |
| scarp |
| seal off(verb, expression, phrasal verb) |
| siege(noun, obstruction, stoppage, barrier, blockade) |
| snag(noun, trouble, help, open, disorder) |
| stonewall(verb, stop, close, check, halt) |
| stop up(expression, stop, control, close, halt) |
| stopper(verb, stop, close, check, halt) |
| stymie(verb, stop, close, check, halt) |
| trammel(noun, verb, close, check, disorder) |
| vallum |
| ward(noun, verb, cover, position, defend) |