The Collaborative International Dictionary of English v.0.48:

Prosperity \Pros*per"i*ty\, n. [F. prosp['e]rit['e], L.
   prosperitas. See Prosperous.]
   The state of being prosperous; advance or gain in anything
   good or desirable; successful progress in any business or
   enterprise; attainment of the object desired; good fortune;
   success; as, commercial prosperity; national prosperity.
   [1913 Webster]

         Now prosperity begins to mellow.         --Shak.
   [1913 Webster]

         Prosperities can only be enjoyed by them who fear not
         at all to lose them.                     -- Jer.
                                                  Taylor.
   [1913 Webster]

   Syn: Prosperousness; thrift; weal; welfare; well being;
        happiness.
        [1913 Webster]

WordNet (r) 3.0 (2006):

prosperity
    n 1: an economic state of growth with rising profits and full
         employment
    2: the condition of prospering; having good fortune [syn:
       prosperity, successfulness]