Source : Webster's Revised Unabridged Dictionary (1913)

Escuage \Es"cu*age\ (?; 48), n. [OF. escuage, F. ['e]cuage, from
   OF. escu shield, F. ['e]cu. See {Esquire}.] (Feud. Law)
   Service of the shield, a species of knight service by which a
   tenant was bound to follow his lord to war, at his own
   charge. It was afterward exchanged for a pecuniary
   satisfaction. Called also {scutage}. --Blackstone.