Esnecy

from The Collaborative International Dictionary of English v.0.48

Esnecy \Es"ne*cy\, n. [See {Eigne}.] (Eng. Law)
   A prerogative given to the eldest coparcener to choose first
   after an inheritance is divided. --Mozley & W.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

ESNECY. Eldership. In the English law, this word signifies the right which 
the eldest coparcener of lands has to choose one of the parts of the estate 
after it has been divided.

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