The Collaborative International Dictionary of English v.0.48:

Feverish \Fe"ver*ish\, a.
   1. Having a fever; suffering from, or affected with, a
      moderate degree of fever; showing increased heat and
      thirst; as, the patient is feverish.
      [1913 Webster]

   2. Indicating, or pertaining to, fever; characteristic of a
      fever; as, feverish symptoms.
      [1913 Webster]

   3. Hot; sultry. "The feverish north." --Dryden.
      [1913 Webster]

   4. Disordered as by fever; excited; restless; as, the
      feverish condition of the commercial world.

   Syn: fevered.
        [1913 Webster]

              Strive to keep up a frail and feverish being.
                                                  --Milton.
        -- Fe"ver*ish*ly, adv. -- Fe"ver*ish*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

feverish
    adj 1: marked by intense agitation or emotion; "worked at a
           feverish pace" [syn: feverish, hectic]
    2: of or relating to or characterized by fever; "a febrile
       reaction caused by an allergen" [syn: febrile, feverish]
       [ant: afebrile]
    3: having or affected by a fever [syn: feverish, feverous]

Moby Thesaurus II by Grady Ward, 1.0:

145 Moby Thesaurus words for "feverish":
   ablaze, afire, agitated, ardent, at fever pitch, baking,
   blistering, boiling, boiling over, breathless, broiling, burning,
   burning hot, burning with excitement, canicular, cordial, cursory,
   delirious, discomposed, disquieted, disturbed, drunk, ebullient,
   enthusiastic, excited, expeditious, exuberant, fanatical, febrile,
   fervent, fervid, festinate, fevered, feverous, fidgety, fiery,
   flaming, flurried, flushed, flustered, flying, frantic, frenetic,
   frenzied, furious, glowing, grilling, hasty, hearty, heated,
   hectic, het up, high-strung, hot, hot as fire, hot as hell,
   hot-blooded, hurried, hyperpyretic, hyperthermic, hysteric,
   immediate, impassioned, in a fever, in rut, infatuated, inflamed,
   insane, instant, intense, intoxicated, jittery, jumpy, keen,
   keyed up, last-minute, like a furnace, like an oven, lively,
   nervous, nervy, on fire, on the spot, overanxious, overdesirous,
   overeager, overenthusiastic, overheated, overwarm, overwrought,
   overzealous, parching, passing, passionate, perfervid, perturbed,
   piping hot, prompt, pyretic, quick, red-hot, restless, roasting,
   ruffled, scalding, scorching, searing, seething, sexually excited,
   shaken, shaken up, simmering, sizzling hot, slap-bang, slapdash,
   smoking hot, snap, speedy, steaming, steamy, stirred up, sudorific,
   superficial, sweating, sweaty, sweltering, sweltry, swift,
   toasting, torrid, troubled, troublous, turbulent, ultrazealous,
   uneasy, unpeaceful, unquiet, unrestrained, upset, urgent, vigorous,
   warm, white-hot, wild, zealous