perpetuity

noun | \ ˌpər-pə-ˈtü-ə-tē, -ˈtyü- \ | per·pe·tu·i·ty

1. : the quality, state, or duration of being perpetual devised to them in perpetuity

2. a : the condition of a future estate limited in such a way as not to vest within the period fixed by law for the vesting of an estate; also : a limitation that gives rise to such a situation : a limitation that gives rise to such a situation

   b : an estate that will not vest within the period fixed by law — see also rule against perpetuities, statutory rule against perpetuities

3. : an annuity payable forever