| catch(noun, disorder, difficulty, weakness, restraint) |
| constipation(noun, hindrance) |
| cover(noun, shade, care, guard, shield) |
| defense(noun, support, care, restraint, guard) |
| earthwork(noun, support, keep, defense, fortification) |
| entanglement(noun, difficulty, hindrance, snag) |
| fortress(noun, support, defense, fortification, stronghold) |
| frontier(noun, border, borderline) |
| guard(noun, support, care, shield, shelter) |
| impasse(noun, hindrance, jam, obstruction, deadlock) |
| jam(noun, block, hindrance, lump, obstacle) |
| parapet(noun, support, block, bar, protection) |
| preventive(noun, difficulty, hindrance, obstacle, obstruction) |
| rail(bar, prison, fence, wall) |
| stumbling-block |
| backstop |
| bank |
| barrage |
| bastion(noun, support, protection, defense, fortification) |
| battlement(support, keep, defense, barricade, wall) |