stopcock vs water pipe

stopcock

noun
  • A valve, tap or faucet which regulates the flow of liquid or gas through a pipe. 

  • A main shutoff for water to a home from a municipal supply. Usually these valves exist in pairs, one outside the property boundary and one inside the property boundary. 

verb
  • To control the gas pressure in (an oil well) by keeping the well closed in and the gas confined except during set intervals when the oil is flowed or pumped. 

water pipe

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

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

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