Equipollence \E`qui*pol"lence\, Equipollency \E`qui*pol"len*cy\, n. [Cf. F. ['e]quipollence. See {Equipollent}.] 1. Equality of power, force, signification, or application. --Boyle. 2. (Logic) Sameness of signification of two or more propositions which differ in language.