bellflower vs tocsin

bellflower

noun
  • A flower of one of these plants, which is shaped like a bell. 

  • Any flowering plants in the genus Campanula. 

  • Flowering plants in the genera, Campanulastrum, Codonopsis, or Platycodon, in the family Campanulaceae. 

  • Any flowering plant in genus Uvularia. 

tocsin

noun
  • A bell used to sound an alarm. 

  • An alarm or other signal sounded by a bell or bells, originally especially with reference to France. 

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