knock vs starboard

knock

verb
  • To rap one's knuckles against something, especially wood. 

  • To criticize verbally; to denigrate; to undervalue. 

  • To kick a ball towards another player; to pass. 

noun
  • An abrupt rapping sound, as from an impact of a hard object against wood. 

  • A sharp impact. 

  • A batsman's innings. 

  • A blow or setback. 

  • Preignition, a type of abnormal combustion occurring in spark ignition engines caused by self-ignition; also, the characteristic knocking sound associated with it. 

  • Synonym of hunger knock 

  • A criticism. 

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 knock and starboard occurred in a corpus of books? (source: Google Ngram Viewer )