hydro vs hydroaeroplane

hydro

noun
  • hydroelectric power 

  • electrical power supply; specifically, electrical power provided by a utility (as a publicly-owned one); payment or bills for this. 

adj
  • hydroelectric 

  • hydroponic 

hydroaeroplane

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