duct vs snorkel

duct

noun
  • a tube or elongated cavity (such as a xylem vessel) for conveying water, sap, or air 

  • a vessel for conveying lymph or glandular secretions such as tears or bile 

  • a pipe, tube or canal which carries gas or liquid from one place to another 

  • a layer (as in the atmosphere or the ocean) which occurs under usually abnormal conditions and in which radio or sound waves are confined to a restricted path 

  • an enclosure or channel for electrical cable runs, telephone cables, or other conductors 

verb
  • to enclose in a duct 

  • to channel something (such as a gas) or propagate something (such as radio waves) through a duct or series of ducts 

snorkel

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

  • A snorkel parka. 

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

verb
  • To use a snorkel. 

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