Umpire
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
When matters in dispute are Submitted to two or more arbitrators, and they do not agree in their decision, it is usual for another person to be called in as "umpire," to whose sole judgment it is then referred.
Brown. And sce Ingraham v. Whitmore, 75 111. 30; Tyler v. Webb, 10 B. Mon. (Ky.) 123; Lyon v. Blossom, 4 Duer (N. Y.) 325.