An Etymological Dictionary of Astronomy and Astrophysics

1. Of or relating to possession or ownership.
   

   2. having or showing an excessive desire to possess, control, or dominate.
      

   3. Denoting an inflected form of a noun or pronoun used to convey the idea of possession, association, etc.; the possessive case (Dictionary.com).

Etymology (EN): → possess; → -tion.