occasion vs solar day

occasion

noun
  • The time when something happens. 

  • Need; requirement, necessity. 

  • Something which causes something else; a cause. 

  • A reason or excuse; a motive; a persuasion. 

  • A special event or function. 

  • A particular happening; an instance or time when something occurred. 

  • An occurrence or state of affairs which causes some event or reaction; a motive or reason. 

  • A favorable opportunity; a convenient or timely chance. 

verb
  • To cause; to produce; to induce 

solar day

noun
  • one day of solar time, the time between successive noons; the time in which a planet such as Earth apparently rotates once around its axis, relative to the sun (on Earth about 24 hours as an average - the length of solar day is not constant throughout the year) 

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