Source : Webster's Revised Unabridged Dictionary (1913)

Crack \Crack\ (kr[a^]k), v. t. [imp. & p. p. {Cracked}
   (kr[a^]kt); p. pr. & vb. n. {Cracking}.] [OE. cracken,
   craken, to crack, break, boast, AS. cracian, cearcian, to
   crack; akin to D. kraken, G. krachen; cf. Skr. garj to
   rattle, or perh. of imitative origin. Cf. {Crake},
   {Cracknel}, {Creak}.]
   1. To break or burst, with or without entire separation of
      the parts; as, to crack glass; to crack nuts.

   2. To rend with grief or pain; to affect deeply with sorrow;
      hence, to disorder; to distract; to craze.

            O, madam, my old heart is cracked.    --Shak.

            He thought none poets till their brains were
            cracked.                              --Roscommon.

   3. To cause to sound suddenly and sharply; to snap; as, to
      crack a whip.

   4. To utter smartly and sententiously; as, to crack a joke.
      --B. Jonson.

   5. To cry up; to extol; -- followed by up. [Low]

   {To crack a bottle}, to open the bottle and drink its
      contents.

   {To crack a crib}, to commit burglary. [Slang]

   {To crack on}, to put on; as, to crack on more sail, or more
      steam. [Colloq.]

Cracked \Cracked\ (kr[a^]kt), a.
   1. Coarsely ground or broken; as, cracked wheat.

   2. Crack-brained. [Colloq.]

Source : WordNet®

cracked
     adj 1: used of skin roughened as a result of cold or exposure;
            "chapped lips" [syn: {chapped}, {roughened}]
     2: broken without being divided into parts but having fissures
        appear on the surface; "a cracked mirror"
     3: of paint or varnish; having the appearance of alligator hide
        [syn: {alligatored}]
     4: informal or slang terms for mentally irregular; "it used to
        drive my husband balmy" [syn: {balmy}, {barmy}, {bats}, {batty},
         {bonkers}, {buggy}, {crackers}, {daft}, {dotty}, {fruity},
         {haywire}, {kooky}, {kookie}, {loco}, {loony}, {loopy}, {nuts},
         {nutty}, {round the bend}, {around the bend}, {wacky}, {whacky}]