degeneration vs reflux

degeneration

noun
  • A thing that has degenerated. 

  • The process or state of growing worse, or the state of having become worse. 

  • That condition of a tissue or an organ in which its vitality has become either diminished or perverted; a substitution of a lower for a higher form of structure. 

  • Gradual deterioration, from natural causes, of any class of animals or plants or any particular organ or organs; hereditary degradation of type. 

reflux

noun
  • The backwards flow of any fluid. 

  • A technique, using a reflux condenser, allowing one to boil the contents of a vessel over an extended period. 

  • The leaking of stomach acid up into the oesophagus. 

verb
  • To boil a liquid in a vessel having a reflux condenser 

  • To flow back or return. 

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