mortmain

Etymology

From Anglo-Norman mortmayn, morte meyn, from Old French mortes meins, after Late Latin phrase mortua manus. See Latin mortuus (“dead”) + manus (“hand”).

noun

1. (law) The perpetual, inalienable possession of lands by a corporation or non-personal entity such as a church.
   1824, Charter of Incorporation of the Royal Asiatic Society of Great Britain and Ireland, [W]e do hereby grant our especial license and authority unto all and every person […] to grant sell alien and convey in mortmain unto and to the use of the said Society and their successors […]
   Though in truth it was the law of mortmain […] which originally sent the founders of chantries to seek the king's licence […] 1900, Frederic William Maitland, “The Corporation Sole”, in Law Quarterly Review, volume 16
2. (literary) A strong and inalienable possession.
   […]; and some part of that influence [of the government], which would otherwise have been possessed as in a sort of mortmain and unalienable domain, returned again to the great ocean from whence it arose, […] 1770, Edmund Burke, Thoughts on the Present Discontents, and Speeches