sundown vs vespers

sundown

noun
  • Sunset. 

  • A hat with a wide brim to shade the eyes from sunlight. 

verb
  • to experience an episode or an onset of some detrimental mental condition like agitation, anxiety, hallucination or dementia, daily at nightfall. 

vespers

noun
  • The sixth of the seven canonical hours, an evening prayer service 

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