air conditioner vs conditioner

air conditioner

noun
  • A machine that is used to control temperature and humidity in an enclosed space. 

conditioner

noun
  • An agricultural machine that crimps and crushes newly cut hay to promote faster and more even drying. 

  • someone who trains athletes or racehorses 

  • hair conditioner 

  • fabric conditioner, fabric softener 

  • anything that improves the condition of something 

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