due date vs maturity

due date

noun
  • The date of payment in financial arrangements. 

  • The date on which a pregnant woman is expected to give birth. 

  • The date by which a book (or other item) borrowed from a library must be returned. 

  • The date by which a task is supposed to be completed. 

maturity

noun
  • Date when payment is due. 

  • The state of being mature, ready or ripe. prime state of productibility and self expression. 

  • When bodily growth has completed and/or reproduction can begin. 

  • The state of a debt obligation at the end of the term of maturation thereof, once all interest and any applicable fees have accrued to the principal. 

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