We attribute the valence electron part of 𝜒̅ (𝒓) to electronegativity and show how this concept can be quantified for regions of space in turn associated with atoms inside materials (molecules and crystals). Discussions on electronegativity inversion upon bond formation is argued to be a natural consequence of our choice of definition for this descriptor. We refer to previous work for a more in-depth analysis and discussion of electronegativity as the average electron energy in general, and its relation to the chemical potential. We consider the development presented herein important also to demonstrate the potential benefits of combining the sometimes historically disparate approaches of quantum chemical topology and MO theory.