debenture vs season ticket

debenture

noun
  • A certificate that certifies an amount of money owed to someone; a certificate of indebtedness. 

  • A type of debt instrument secured only by the general credit or promise to pay of the issuer, not involving any physical assets or collateral, now commonly issued by large, well established corporations with adequate credit ratings. 

  • A document granting lenders a charge over a borrower’s physical assets, giving them a means to collect a debt, as part of a secured loan. 

season ticket

noun
  • A ticket that is valid for all of the events in a series of related events for which individual tickets would otherwise be needed. 

  • A ticket that is valid for multiple rides (limited by number of rides and/or time of travel) by public transit for which individual tickets would otherwise be needed. 

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