prophylactic vs unsterile

prophylactic

adj
  • Serving to prevent or protect against an undesired effect, especially disease or pregnancy 

noun
  • A medicine which preserves or defends against disease; a preventive. 

  • Any device or mechanism intended to prevent harmful consequences. 

  • A prophylactic condom. 

unsterile

adj
  • Not sterile 

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