seisin

noun3

1. •
   (historical) An entitlement to a freehold estate with a right to immediate possession.
2. •
   (no longer used) The act of taking possession.
3. •
   (no longer used) The thing possessed; property.

   • Disseisin is a large Title, and is an unlawful Entry and Ouster of him that has an actual Seisin and Freehold. — 1713