catwalk vs gangboard

catwalk

noun
  • An elevated enclosed passage providing access fore and aft from the bridge of a merchant vessel. 

  • A narrow elevated stage on which models parade; a runway 

  • Any similar elevated walkway. 

  • The business of making clothes for fashion shows. 

gangboard

noun
  • A board or plank placed within or without the bulwarks of a vessel's waist for lookouts to walk or stand on. 

  • The boards ending the hammock-nettings at either side of the entrance from the accommodation-ladder to the deck. 

  • A board or plank used as a temporary footbridge between a ship and a dockside or any gap such as scaffolding. 

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