blooper vs bollard

blooper

noun
  • A gaff-rigged fore-and-aft sail set from and aft of the aftmost mast of a square-rigged ship; a spanker. 

  • A fly ball that is weakly hit just over the infielders. 

  • The Vietnam-era M79 grenade launcher (due to its distinctive report). 

  • A filmed or videotaped outtake that has recorded an amusing accident and/or mistake. 

  • A blunder, an error. 

bollard

noun
  • A strong vertical post of timber or iron, fixed to the ground and/or on the deck of a ship, to which the ship's mooring lines etc are secured. 

  • A similar post preventing vehicle access to a pedestrian area, to delineate traffic lanes, or used for security purposes. 

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