[1] : The Collaborative International Dictionary of English v.0.48

halfcock \half"cock`\ -ko^k`, v. t. imp.  p. p.
   halfcocked-ko^kt; p. pr.  vb. n. halfcocking.
   to set the cock of a firearm at the first notch.
   1913 webster

   to go off half-cocked, to go off halfcocked.
   a to be discharged prematurely, or with the trigger at half
       cock; -- said of a firearm.
   b to do or say something without due thought or care.
       colloq. or low
       1913 webster
see also:
halfcocked halfcocking to go off half-cocked to go off halfcocked 

[2] : WordNet (r) 2.0

half-cock
     n : confusion resulting from lack of preparation

Halfcock >> H Words
Halfcock, definition of term: Halfcock
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