caesura vs interval

caesura

noun
  • A break of an era or other measure of history and time; where one era ends and another begins; turning point. 

  • Using two words to divide a metrical foot. 

  • A pause or interruption in a poem, music, building, or other work of art. 

  • The caesura mark ‖ or ||. 

interval

noun
  • A period of time. 

  • A connected section of the real line which may be empty or have a length of zero. 

  • An intermission. 

  • half time, a scheduled intermission between the periods of play 

  • The difference (a ratio or logarithmic measure) in pitch between two notes, often referring to those two pitches themselves (otherwise known as a dyad). 

  • Either of the two breaks, at lunch and tea, between the three sessions of a day's play 

  • A distance in space. 

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