crackajack

from The Collaborative International Dictionary of English v.0.48

Crackajack \Crack"a*jack`\, a. [Now usually spelled
   {crackerjack}.]
   Of marked ability or excellence. [Slang]
   [Webster 1913 Suppl. +PJC] crackbrained

from The Collaborative International Dictionary of English v.0.48

Crackajack \Crack"a*jack`\, n. [Now usually spelled
   {crackerjack}.] [prob. from crack + jack, a man.]
   1. An individual of marked ability or excellence, esp. in
      some sport; as, he is a crackajack at tennis. [Slang]
      [Webster 1913 Suppl.]

   2. A preparation of popped corn, candied and pressed into
      small cakes. [U. S.]
      [Webster 1913 Suppl. +PJC]

from The Collaborative International Dictionary of English v.0.48

Crackerjack \Crack"er*jack`\, a. [also spelled {crackajack}.]
   Of marked ability or excellence. [Slang]
   [Webster 1913 Suppl. +PJC]

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