IPA: /ˈmɔːrtmeɪn/
KK: /mɔrtˈmeɪn/
A legal term referring to the permanent ownership of property, especially by institutions like churches, that cannot be sold or transferred.
The church held its land in mortmain, ensuring it would remain under its control forever.
Mortmain is formed from "mort" (from Old French, meaning dead) and "main" (from Latin "manus", meaning hand). The term originally referred to property that was held in perpetuity by a religious institution, thus 'dead hand' signifying that it could not be transferred or inherited.
Think of 'mort' meaning dead and 'main' meaning hand — together they describe a 'dead hand' that cannot pass on property.