OUSTER (from Anglo-Fr. ouster, to remove, take away, O. Fr. aster, mod. Fr. oter, Eng. " oust," to eject, exclude; the derivation is not known; Lat. ohstare, to stand in the way of, resist, would give the form but does not suit the sense; a more probable suggestion connects with a supposed haustare, from hour ire, to draw water; cf. " exhaust "), a legal term signifying dispossession, especially the wrong or injury suffered by a person dispossessed of freeholds or chattels real. The wrong-doer by getting into occupation forces the real owner to take legal steps to regain his rights. Ouster of the freehold may be effected by abatement; i.e. by entry on the death of the person seized before the entry of the heir, or devisee, by intrusion, entry after the death of the tenant for life before the entry of the reversioner or remainderman, by disseisin, the forcible or fraudulent expulsion of the occupier or person seized of the property. Ouster of chattels real is effected by disseisin, the turning out by force or fraud of the legal proprietor before his estate is determined- In feudal law, the term ouster-le-main (Lat. amovere manum, to take away the hand) was applied to a writ or judgment granting the livery of land out of the sovereign's hand on the plea that he has no title to it, and also to the delivery by a guardian of land to a ward on his coming of age.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)