the planking or plating along the sides of a nautical vessel above her gunwale that reduces the likelihood of seas washing over the gunwales and people being washed overboard
an embankment built around a space for defensive purposes; "they stormed the ramparts of the city"; "they blew the trumpet and the walls came tumbling down"
A bulwark against something protects you against it. A bulwark of something protects it. The abbeys were founded in the 12th century by King David as a bulwark against the English
[ 'bul-(")w&rk, -"work; 'b&a ] (noun.) 15th century. Middle English bulwerke, from Middle Dutch bolwerc, from Middle High German, from bole plank + werc work.