In firearms terms, headspace refers to the distance between the bolt face and chamber necessary for reliable functioning of the weapon, or as a verb, the mechanism by which the correct positioning is achieved.
Example Usage of Headspace
courageinc: You ever feel like you and the rest of the world exist in different places...that your Headspace is somewhere in lalaland?
robdewey: Playing tonight at the Artists' Quarter with Headspace. 7:30-9:30pm. No cover.
degroteoptimist: eindelijk mijn 'Headspace' gevuld met All-in-One SEO voor WordPress