n. [ Ir. tanaiste, tanaise, second, the second person in rank, the presumptive or apparent heir to a prince. ] In Ireland, a lord or proprietor of a tract of land or of a castle, elected by a family, under the system of tanistry. [ 1913 Webster ]

This family [ the O'Hanlons ] were tanists of a large territory within the present county of Armagh. M. A. Lower. [ 1913 Webster ]

n. [ See Tanist. ] In Ireland, a tenure of family lands by which the proprietor had only a life estate, to which he was admitted by election. [ 1913 Webster ]

☞ The primitive intention seems to have been that the inheritance should descend to the oldest or most worthy of the blood and name of the deceased. This was, in reality, giving it to the strongest; and the practice often occasioned bloody feuds in families, for which reason it was abolished under James I. [ 1913 Webster ]