Tan"ist (?), 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.
This family [the O'Hanlons] were tanists of a large territory within the present county of Armagh.
M. A. Lower.
© Webster 1913.