renege vs warrant

renege

verb
  • To break a promise or commitment; to go back on one's word. 

  • In a card game, to break one's commitment to follow suit when capable. 

warrant

verb
  • To guarantee as being true; (colloquial) to believe strongly. 

  • To justify; to give grounds for. 

  • To authorize; to give (someone) sanction or warrant (to do something). 

  • To guarantee (something) to be (of a specified quality, value, etc.). 

noun
  • Authorization or certification; a sanction, as given by a superior. 

  • A certificate of appointment given to a warrant officer. 

  • A judicial writ authorizing an officer to make a search, seizure, or arrest, or to execute a judgment. 

  • An option, usually issued together with another security and with a term at issue greater than a year, to buy other securities of the issuer. 

  • Something that provides assurance or confirmation; a guarantee or proof. 

  • Underclay in a coal mine. 

  • A document certifying that a motor vehicle meets certain standards of mechanical soundness and safety; a warrant of fitness. 

  • An order that serves as authorization; especially a voucher authorizing payment or receipt of money. 

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