The Collaborative International Dictionary of English v.0.48:

Crazy \Cra"zy\ (kr[=a]"z[y^]), a. [From Craze.]
   1. Characterized by weakness or feebleness; decrepit; broken;
      falling to decay; shaky; unsafe.
      [1913 Webster]

            Piles of mean andcrazy houses.        --Macaulay.
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            One of great riches, but a crazy constitution.
                                                  --Addison.
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            They . . . got a crazy boat to carry them to the
            island.                               --Jeffrey.
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   2. Broken, weakened, or dissordered in intellect; shattered;
      demented; deranged.
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            Over moist and crazy brains.          --Hudibras.
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   3. Inordinately desirous; foolishly eager. [Colloq.]
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            The girls were crazy to be introduced to him. --R.
                                                  B. Kimball.
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   Crazy bone, the bony projection at the end of the elbow
      (olecranon), behind which passes the ulnar nerve; -- so
      called on account of the curiously painful tingling felt,
      when, in a particular position, it receives a blow; --
      called also funny bone.

   Crazy quilt, a bedquilt made of pieces of silk or other
      material of various sizes, shapes, and colors, fancifully
      stitched together without definite plan or arrangement.
      [1913 Webster]

WordNet (r) 3.0 (2006):

crazy
    adj 1: affected with madness or insanity; "a man who had gone
           mad" [syn: brainsick, crazy, demented, disturbed,
           mad, sick, unbalanced, unhinged]
    2: foolish; totally unsound; "a crazy scheme"; "half-baked
       ideas"; "a screwball proposal without a prayer of working"
       [syn: crazy, half-baked, screwball, softheaded]
    3: possessed by inordinate excitement; "the crowd went crazy";
       "was crazy to try his new bicycle"
    4: bizarre or fantastic; "had a crazy dream"; "wore a crazy hat"
    5: intensely enthusiastic about or preoccupied with; "crazy
       about cars and racing"; "he is potty about her" [syn:
       crazy, wild, dotty, gaga]
    n 1: someone deranged and possibly dangerous [syn: crazy,
         loony, looney, nutcase, weirdo]

Moby Thesaurus II by Grady Ward, 1.0:

239 Moby Thesaurus words for "crazy":
   abnormal, absurd, anamorphous, ape, apish, arrested, asinine,
   askew, asymmetric, avid, babbling, backward, balmy, bananas, barmy,
   bats, batty, befooled, beguiled, bent, bereft of reason, besotted,
   beyond belief, bicolor, bicolored, big, bizarre, blithering,
   bonkers, bowed, brainless, brainsick, buffoonish, burbling,
   certifiable, cockamamie, cockeyed, colorful, colory, contorted,
   crackbrained, cracked, crackers, crackpot, crazed, credulous,
   cretinistic, cretinous, crooked, crumpled, crunched, cuckoo,
   daedal, daffy, daft, damned, dazed, deluded, demented,
   deprived of reason, deranged, deviative, dichromatic, dippy,
   disoriented, distorted, distraught, dithering, divers-colored,
   dizzy, doting, dotty, dreadful, driveling, drooling, dumb, eager,
   enthusiastic, erratic, excited, extravagant, fantastic, fatuitous,
   fatuous, flaked-out, flaky, flighty, fond, fool, foolheaded,
   foolish, fuddled, futile, gaga, goofy, grotesque, gulled,
   half-baked, half-witted, hallucinated, harebrained, harlequin,
   high-flown, idiotic, ill-considered, imbecile, imbecilic,
   impracticable, impractical, imprudent, inane, incredible, inept,
   infatuated, insane, irrational, irregular, kaleidoscopic, keen,
   keen on, kooky, labyrinthine, larruping, laughable, lawful, loco,
   loony, lopsided, ludicrous, lunatic, mad, maddened, main, maniac,
   manic, many-colored, maudlin, maundering, mazed, medley, mental,
   mentally defective, mentally deficient, mentally handicapped,
   mentally retarded, meshuggah, mongoloid, monstrous, moon-struck,
   moonstruck, moronic, motley, multicolor, multicolored,
   multicolorous, non compos, non compos mentis, nonsensical,
   nonsymmetric, not all there, not right, nuts, nutty, odd,
   of unsound mind, off, one-sided, outrageous, outre, parti-color,
   parti-colored, pointless, polychromatic, polychrome, polychromic,
   poppycockish, possessed, potty, preposterous, prismal, psycho,
   queer, rash, reasonless, reckless, retarded, ridiculous, risible,
   round the bend, sappy, screwball, screwy, senseless, sentimental,
   shot, shot through, sick, silly, simple, simpleminded,
   simpletonian, slobbering, spectral, sprung, stark-mad,
   stark-staring mad, strange, stupid, subnormal, tetched,
   thoughtless, thunder and lightning, tortuous, touched,
   trichromatic, trichromic, tricolor, tricolored, twisted, two-tone,
   unbalanced, unhinged, unsane, unsettled, unsound, unsymmetric,
   unworkable, varicolored, variegated, versicolor, versicolored,
   wacky, wandering, warped, weird, wet, wild, witless, zealous