The Collaborative International Dictionary of English v.0.48:

Alleviate \Al*le"vi*ate\, v. t. [imp. & p. p. Alleviated; p.
   pr. & vb. n. Alleviating.] [LL. alleviare, fr. L. ad +
   levis light. See Alegge, Levity.]
   1. To lighten or lessen the force or weight of. [Obs.]
      [1913 Webster]

            Should no others join capable to alleviate the
            expense.                              --Evelyn.
      [1913 Webster]

            Those large bladders . . . conduce much to the
            alleviating of the body [of flying birds]. --Ray.
      [1913 Webster]

   2. To lighten or lessen (physical or mental troubles); to
      mitigate, or make easier to be endured; as, to alleviate
      sorrow, pain, care, etc.; -- opposed to aggravate.
      [1913 Webster]

            The calamity of the want of the sense of hearing is
            much alleviated by giving the use of letters. --Bp.
                                                  Horsley.
      [1913 Webster]

   3. To extenuate; to palliate. [R.]
      [1913 Webster]

            He alleviates his fault by an excuse. --Johnson.
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   Syn: To lessen; diminish; soften; mitigate; assuage; abate;
        relieve; nullify; allay.

   Usage: To Alleviate, Mitigate, Assuage, Allay. These
          words have in common the idea of relief from some
          painful state; and being all figurative, they differ
          in their application, according to the image under
          which this idea is presented. Alleviate supposes a
          load which is lightened or taken off; as, to alleviate
          one's cares. Mitigate supposes something fierce which
          is made mild; as, to mitigate one's anguish. Assuage
          supposes something violent which is quieted; as, to
          assuage one's sorrow. Allay supposes something
          previously excited, but now brought down; as, to allay
          one's suffering or one's thirst. To alleviate the
          distresses of life; to mitigate the fierceness of
          passion or the violence of grief; to assuage angry
          feeling; to allay wounded sensibility.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

alleviated \alleviated\ adj.
   1. 1 made less severe or intense. unmitigated

   Syn: eased, relieved, mitigated.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

alleviated
    adj 1: (of pain or sorrow) made easier to bear [syn:
           alleviated, eased, relieved]