fail vs regress

fail

verb
  • To be wanting; to fall short; to be or become deficient in any measure or degree up to total absence. 

  • Not to achieve a particular stated goal. (Usage note: The direct object of this word is usually an infinitive.) 

  • To become unable to meet one's engagements; especially, to be unable to pay one's debts or discharge one's business obligation; to become bankrupt or insolvent. 

  • To receive one or more non-passing grades in academic pursuits. 

  • To give a student a non-passing grade in an academic endeavour. 

  • To be wanting to, to be insufficient for, to disappoint, to desert; to disappoint one's expectations. 

  • To neglect. 

  • To be unsuccessful. 

  • Of a machine, etc.: to cease to operate correctly. 

adj
  • Unsuccessful; inadequate; unacceptable in some way. 

noun
  • A failure, especially of a financial transaction (a termination of an action). 

  • A failure (condition of being unsuccessful). 

  • A failing grade in an academic examination. 

  • Poor quality; substandard workmanship. 

  • A failure (something incapable of success). 

  • A piece of turf cut from grassland. 

regress

verb
  • To move backwards to an earlier stage; to devolve. 

  • To move from east to west. 

  • To perform a regression on an explanatory variable. 

  • To interrogate a person in a state of trance about forgotten elements of their past. 

noun
  • The act of passing back; passage back; return; retrogression. 

  • In property law, the right of a person (such as a lessee) to return to a property. 

  • The power or liberty of passing back. 

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