prostration vs somnolence

prostration

noun
  • Being laid face down (prone). 

  • A part of the ordination of Catholic and Orthodox priests. 

  • The act or condition of prostrating oneself (lying flat), as a sign of humility. 

  • The condition of being prostrated, as from heat; complete loss of strength. 

  • A reverential bow performed in Middle Eastern cultures. 

somnolence

noun
  • A state of drowsiness or sleepiness. 

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