inexhaustible vs prolific

inexhaustible

adj
  • Impossible to exhaust; unlimited. 

prolific

adj
  • Similarly producing results or performing deeds in abundance 

  • Fertile; producing offspring or fruit in abundance — applied to plants producing fruit, animals producing young, etc. 

  • Of a flower: from which another flower is produced. 

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