Source : Webster's Revised Unabridged Dictionary (1913)

Expectation \Ex`pec*ta"tion\n. [L. expectio. exspectio: cf. F.
   expectation.]
   1. The act or state of expecting or looking forward to an
      event as about to happen. ``In expectation of a guest.''
      --Tennyson.

            My soul, wait thou only upon God, for my expectation
            is from him.                          --Ps. lxii. 5.

   2. That which is expected or looked for.

            Why our great expectation should be called The seed
            of woman.                             --Milton.

   3. The prospect of the future; grounds upon which something
      excellent is expected to happen; prospect of anything good
      to come, esp. of property or rank.

            His magnificent expectations made him, in the
            opinion of the world, the best match in Europe.
                                                  --Prescott.

            By all men's eyes a youth of expectation. --Otway.

   4. The value of any chance (as the prospect of prize or
      property) which depends upon some contingent event.
      Expectations are computed for or against the occurrence of
      the event.

   5. (Med.) The leaving of the disease principally to the
      efforts of nature to effect a cure.

   {Expectation of life}, the mean or average duration of the
      life individuals after any specified age.

   Syn: Anticipation; confidence; trust.

Source : WordNet®

expectation
     n 1: belief about (or mental picture of) the future [syn: {outlook},
           {prospect}]
     2: wishing with confidence of fulfillment [syn: {anticipation}]
     3: the feeling that something is about to happen
     4: the sum of the values of a random variable divided by the
        number of values [syn: {arithmetic mean}, {first moment},
        {expected value}]