hookah vs water pipe

hookah

noun
  • A pipe with a long flexible tube that draws the smoke through water, traditionally used for smoking tobacco, which is often flavored. 

  • A tank-less surface air compressor pump and umbilical piping system that supplies air to a diving mask 

water pipe

noun
  • A device for smoking, such as a hookah or bong, in which the smoke is drawn through a container of water before inhaling. 

  • A pipe that is a conduit for water; an essential element of plumbing. 

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