1. [informal] One's mental state or mindset
   "She needed to get into the right headspace before the performance"
    
2. The volume left at the top of a filled container (bottle, jar or tin) before sealing
   "Proper headspace is crucial for safe canning"
    
3. (firearms) the distance between the breech face and the part of the chamber that stops forward motion of the cartridge

Derived forms: headspaces

Type of: indefinite quantity

Encyclopedia: Headspace