boat vs snorkel

boat

verb
  • To place in a boat. 

  • To travel by boat. 

  • To transport in a boat. 

noun
  • A craft used for transportation of goods, fishing, racing, recreational cruising, or military use on or in the water, propelled by oars or outboard motor or inboard motor or by wind. 

  • A full house. 

  • One of two possible conformations of cyclohexane rings (the other being chair), shaped roughly like a boat. 

  • A vehicle, utensil, or dish somewhat resembling a boat in shape. 

  • The refugee boats arriving in Australian waters, and by extension, refugees generally. 

snorkel

verb
  • To use a snorkel. 

noun
  • A snorkel parka. 

  • A retractable tube fitted in diesel-engine submarines to allow sufficient ventilation that the engines may be used at periscope depth. 

  • A hollow tube, held in the mouth, or mounted on and opening into a diving mask, used by swimmers for breathing underwater. 

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