The Collaborative International Dictionary of English v.0.48:

Maturity \Ma*tu"ri*ty\, n. [L. maturitas: cf. F. maturit['e].]
   [1913 Webster]
   1. The state or quality of being mature; ripeness; full
      development; as, the maturity of corn or of grass;
      maturity of judgment; the maturity of a plan.
      [1913 Webster]

   2. Arrival of the time fixed for payment; a becoming due;
      termination of the period a note, etc., has to run.
      [1913 Webster]

WordNet (r) 3.0 (2006):

maturity
    n 1: the period of time in your life after your physical growth
         has stopped and you are fully developed [syn: adulthood,
         maturity]
    2: state of being mature; full development [syn: maturity,
       matureness] [ant: immatureness, immaturity]
    3: the date on which an obligation must be repaid [syn:
       maturity, maturity date, due date]