The Collaborative International Dictionary of English v.0.48:

Relieve \Re*lieve"\ (r?-l?v"), v. t. [imp. & p. p. Relieved
   (-l?vd"); p. pr. & vb. n. Relieving.] [OE. releven, F.
   relever to raise again, discharge, relieve, fr. L. relevare
   to lift up, raise, make light, relieve; pref. re- re- +
   levare to raise, fr. levis light. See Levity, and cf.
   Relevant, Relief.]
   1. To lift up; to raise again, as one who has fallen; to
      cause to rise. [Obs.] --Piers Plowman.
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   2. To cause to seem to rise; to put in relief; to give
      prominence or conspicuousness to; to set off by contrast.
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            Her tall figure relieved against the blue sky;
            seemed almost of supernatural height. --Sir W.
                                                  Scott.
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   3. To raise up something in; to introduce a contrast or
      variety into; to remove the monotony or sameness of.
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            The poet must . . . sometimes relieve the subject
            with a moral reflection.              --Addison.
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   4. To raise or remove, as anything which depresses, weighs
      down, or crushes; to render less burdensome or afflicting;
      to alleviate; to abate; to mitigate; to lessen; as, to
      relieve pain; to relieve the wants of the poor.
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   5. To free, wholly or partly, from any burden, trial, evil,
      distress, or the like; to give ease, comfort, or
      consolation to; to give aid, help, or succor to; to
      support, strengthen, or deliver; as, to relieve a besieged
      town.
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            Now lend assistance and relieve the poor. --Dryden.
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   6. To release from a post, station, or duty; to put another
      in place of, or to take the place of, in the bearing of
      any burden, or discharge of any duty.
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            Who hath relieved you?                --Shak.
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   7. To ease of any imposition, burden, wrong, or oppression,
      by judicial or legislative interposition, as by the
      removal of a grievance, by indemnification for losses, or
      the like; to right.
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   Syn: To alleviate; assuage; succor; assist; aid; help;
        support; substain; ease; mitigate; lighten; diminish;
        remove; free; remedy; redress; indemnify.
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WordNet (r) 3.0 (2006):

relieve
    v 1: provide physical relief, as from pain; "This pill will
         relieve your headaches" [syn: relieve, alleviate,
         palliate, assuage]
    2: free someone temporarily from his or her obligations [syn:
       take over, relieve]
    3: grant relief or an exemption from a rule or requirement to;
       "She exempted me from the exam" [syn: exempt, relieve,
       free] [ant: apply, enforce, implement]
    4: lessen the intensity of or calm; "The news eased my
       conscience"; "still the fears" [syn: still, allay,
       relieve, ease]
    5: save from ruin, destruction, or harm [syn: salvage,
       salve, relieve, save]
    6: relieve oneself of troubling information [syn: unbosom,
       relieve]
    7: provide relief for; "remedy his illness" [syn: remedy,
       relieve]
    8: free from a burden, evil, or distress
    9: take by stealing; "The thief relieved me of $100"
    10: grant exemption or release to; "Please excuse me from this
        class" [syn: excuse, relieve, let off, exempt]
    11: alleviate or remove (pressure or stress) or make less
        oppressive; "relieve the pressure and the stress"; "lighten
        the burden of caring for her elderly parents" [syn:
        relieve, lighten]