%mortmain%

n. [ F. mort, morte, dead + main hand; F. main-morte. See Mortal, and Manual. ] (Law) Possession of lands or tenements in, or conveyance to, dead hands, or hands that cannot alienate. [ 1913 Webster ]

☞ The term was originally applied to conveyance of land made to ecclesiastical bodies; afterward to conveyance made to any corporate body. Burrill. [ 1913 Webster ]