Eisnetia
The Cyclopedic Law Dictionary · Walter A. Shumaker and George Foster Longsdorf; ed. James C. Cahill · 1922
The Cyclopedic Law Dictionary
or EINETIA (Lat.) The share of the oldest son; the portion acquired by primogeniture.
Termes de la Ley; Co. Litt. 166b; Cowell.