bulwark vs secure

bulwark

verb
  • To provide protection of defense for something. 

  • To fortify something with a wall or rampart. 

noun
  • A defensive wall or rampart. 

  • A defense or safeguard. 

  • A breakwater. 

  • Any means of defence or security. 

  • 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. 

secure

verb
  • To make safe; to relieve from apprehensions of, or exposure to, danger; to guard; to protect. 

  • To make fast; to close or confine effectually; to render incapable of getting loose or escaping. 

  • To get possession of; to make oneself secure of; to acquire certainly. 

  • To put beyond hazard of losing or of not receiving; to make certain; to assure; frequently with against or from, or formerly with of. 

adj
  • Free from the danger of theft; safe. 

  • Certain to be achieved or gained; assured. 

  • Free from attack or danger; protected. 

  • Free from the risk of eavesdropping, interception or discovery; secret. 

  • Confident in opinion; not entertaining, or not having reason to entertain, doubt; certain; sure; commonly used with of. 

  • Free from anxiety or doubt; unafraid. 

  • Free from the risk of financial loss; reliable. 

  • Firm and not likely to fail; stable. 

How often have the words bulwark and secure occurred in a corpus of books? (source: Google Ngram Viewer )