assault vs bulwark

assault

noun
  • A non-competitive combat between two fencers. 

  • A violent onset or attack with physical means, for example blows, weapons, etc. 

  • A violent verbal attack, for example with insults, criticism, and the like 

  • An act that causes someone to apprehend imminent bodily harm (such as brandishing a weapon). 

  • An attempt to commit battery: a violent attempt, or willful effort with force or violence, to do hurt to another, but without necessarily touching the person, such as by raising a fist in a threatening manner, or by striking at the person and missing. 

  • The tort whose action is such an act. 

  • The crime whose action is such an attempt. 

verb
  • To threaten or harass. 

  • To attack, physically or figuratively; to assail. 

bulwark

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. 

verb
  • To fortify something with a wall or rampart. 

  • To provide protection of defense for something. 

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