sprayer vs sprinkler head

sprayer

noun
  • An object used for spraying, such as a spray bottle. 

  • A device, machine or vehicle used for spraying, where sprayers are commonly used for projection of water, weed killers, crop performance materials, pest maintenance chemicals, as well as manufacturing and production line ingredients. 

  • One who sprays. 

sprinkler head

noun
  • A heat-activated device that sprays water in the event of a fire, usually mounted on a ceiling. 

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