re·ver·sion /ri-'vər-zhən/ n [Anglo-French, from Middle French, from Latin reversio act of turning back, from revertere to turn back]
1: the returning of an estate upon its termination to the former owner or to his or her successor in interest
2 a: the present vested interest in the residue of an estate that remains in its owner after the grant therefrom of a lesser estate (as a life estate) and that will commence in possession by operation of law upon termination of the lesser estate
b: the future interest in property left in a grantor or his or her successor in interest that is not subject to a condition precedent compare possibility of reverter, remainder
re·ver·sion·ary /-zhə-ˌner-ē/ adj
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.