bellflower vs vesper

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. 

vesper

noun

  • The bell that summons worshipers to vespers; the vesper-bell 

  • A vesper bat. 

  • A vesper martini. 

  • The evening. 

adj

  • Evening. 

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