The Collaborative International Dictionary of English v.0.48:

Severalty \Sev"er*al*ty\, n.
   A state of separation from the rest, or from all others; a
   holding by individual right.
   [1913 Webster]

         Forests which had never been owned in severalty.
                                                  --Bancroft.
   [1913 Webster]

   Estate in severalty (Law), an estate which the tenant holds
      in his own right, without being joined in interest with
      any other person; -- distinguished from joint tenancy,
      coparcenary, and common. --Blackstone.
      [1913 Webster]