discontinuity vs endurance

discontinuity

noun
  • a subterranean interface at which seismic velocities change 

  • A lack of continuity, regularity or sequence; a break or gap. 

  • A point in the range of a function at which it is undefined or discontinuous. 

endurance

noun
  • The length of time that a ship's rations will supply 

  • The measure of a person's stamina or persistence. 

  • Ability to endure hardship. 

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