Source : Webster's Revised Unabridged Dictionary (1913)

Archivolt \Ar"chi*volt\, n. [F. archivolte, fr. It. archivolto;
   pref. archi- + volto vault, arch. See {Vault}.] (Arch.)
   (a) The architectural member surrounding the curved opening
       of an arch, corresponding to the architrave in the case
       of a square opening.
   (b) More commonly, the molding or other ornaments with which
       the wall face of the voussoirs of an arch is charged.