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.]

Source : WordNet®

cracking
     adj : very good; "he did a bully job"; "a neat sports car"; "had a
           great time at the party"; "you look simply smashing"
           [syn: {bang-up}, {bully}, {corking}, {dandy}, {great},
           {groovy}, {keen}, {neat}, {nifty}, {not bad(p)}, {peachy},
            {slap-up}, {swell}, {smashing}]
     n 1: a sudden sharp noise; "the crack of a whip"; "he heard the
          cracking of the ice"; "he can hear the snap of a twig"
          [syn: {crack}, {snap}]
     2: the act of cracking something [syn: {fracture}, {crack}]
     3: the process whereby heavy molecules of naphtha or petroleum
        are broken down into hydrocarbons of lower molecular
        weight (especially in the oil-refining process)

Source : Free On-Line Dictionary of Computing

cracking
     
        {cracker}