air freshener vs purgative

air freshener

noun
  • Any of many forms of device containing substances that neutralize or mask unpleasant odours. 

purgative

noun
  • something, such as a substance or medicine, that purges; laxative 

adj
  • purging 

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