recrudescence vs rejuvenation

recrudescence

noun
  • The acute recurrence of a disease, or its symptoms, after a period of improvement. 

  • The condition or state being recrudescent; the condition of something (often undesirable) breaking out again, or re-emerging after temporary abatement or suppression. 

  • The production of a fresh shoot from a ripened spike. 

rejuvenation

noun
  • The process of producing beneficial changes. 

  • The process of rendering young again. 

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