headspace

  1. Noun.  The space between the top of the contents of a container (such as a jar) and its seal (such as a lid).
  2. Noun.  (informal) One's mental state.
  3. Noun.  (context, firearms) The gap between the face of the bolt and the stopping surface for the cartridge.

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This entry was last updated on RefTopia from its source on 3/20/2012.