roof vs starboard

roof

verb
  • To cover or furnish with a roof. 

  • To traverse buildings by walking or climbing across their roofs. 

  • To put into prison, to bird. 

  • To shelter as if under a roof. 

noun
  • The external covering at the top of a building. 

  • The top external level of a building. 

  • The upper part of a cavity. 

  • An overhanging rock wall. 

  • The surface or bed of rock immediately overlying a bed of coal or a flat vein. 

starboard

verb
  • To put to the right, or starboard, side of a vessel. 

noun
  • The righthand side of a ship, boat or aircraft when facing the front, or fore or bow. Used to unambiguously refer to directions according to the sides of the vessel, rather than those of a crew member or object. 

  • One of the two traditional watches aboard a ship standing a watch in two. 

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