aerator vs air cooler

aerator

noun
  • A fumigator used to bleach grain, destroying fungi and insects. 

  • A device which mixes air with a substance, particularly soil or a liquid. 

  • A device used for charging mineral waters with gas and in making soda water. 

air cooler

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