1911 Encyclopædia Britannica/Allodium
ALLODIUM, or Alodium, a legal term for lands which are the absolute property of their owner, and not subject to any service or acknowledgement to a superior. It is thus the opposite of fe-odum or fief. The proper derivation of the word has been much discussed and is still doubtful, though it is probably compounded of all, whole or entire, and odh, property. Allodial tenure seems to have been common throughout northern Europe. It exists in Orkney and Shetland, but is unknown in England, the feudal system having been made universal by William the Conqueror.