Source : Webster's Revised Unabridged Dictionary (1913)

Udal \U"dal\, n. & a. Udalborn \U"dal*born`\, Udaler \U"dal*er\,
Udalman \U"dal*man\, etc.
   Vars. of {Odal}, etc. Obs. exc. in Shetland and the Orkney
   Islands, where udal designates land held in fee simple
   without any charter and free of any feudal character.

Udal \U"dal\ ([=u]"dal), n. [Icel. [=o][eth]al allodium, an
   hereditary estate; akin to Sw. odal allodial, Dan. odel.]
   In Shetland and Orkney, a freehold; property held by udal, or
   allodial, right.

Udal \U"dal\, a.
   Allodial; -- a term used in Finland, Shetland, and Orkney.
   See {Allodial}. --Burrill.