nighttime vs sunlight

nighttime

noun
  • The hours of darkness between sunset and sunrise; the night. 

adj
  • Pertaining to nighttime; appropriate to the night. 

  • Happening during the night. 

sunlight

noun
  • Synonym of sunrise. 

  • All the electromagnetic radiation given off by the Sun, especially that in the visible spectrum that bathes the Earth. 

  • Brightness, hope; a positive outlook. 

verb
  • To work on the side (at a secondary job) during the daytime. 

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