The Collaborative International Dictionary of English v.0.48:

Promise \Prom"ise\, v. t. [imp. & p. p. Promised; p. pr. & vb.
   n. Promising.]
   [1913 Webster]
   1. To engage to do, give, make, or to refrain from doing,
      giving, or making, or the like; to covenant; to engage;
      as, to promise a visit; to promise a cessation of
      hostilities; to promise the payment of money. "To promise
      aid." --Shak.
      [1913 Webster]

   2. To afford reason to expect; to cause hope or assurance of;
      as, the clouds promise rain. --Milton.
      [1913 Webster]

   3. To make declaration of or give assurance of, as some
      benefit to be conferred; to pledge or engage to bestow;
      as, the proprietors promised large tracts of land; the
      city promised a reward.
      [1913 Webster]

   Promised land. See Land of promise, under Land.

   To promise one's self.
      (a) To resolve; to determine; to vow.
      (b) To be assured; to have strong confidence.
          [1913 Webster]

                I dare promise myself you will attest the truth
                of all I have advanced.           --Rambler.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Promising \Prom"is*ing\, a.
   Making a promise or promises; affording hope or assurance;
   as, promising person; a promising day. -- Prom"is*ing*ly,
   adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

promising
    adj 1: showing possibility of achievement or excellence; "a
           promising young man"
    2: full or promise; "had a bright future in publishing"; "the
       scandal threatened an abrupt end to a promising political
       career"; "a hopeful new singer on Broadway" [syn: bright,
       hopeful, promising]