Source : Webster's Revised Unabridged Dictionary (1913)

Architrave \Ar"chi*trave\, n. [F. architrave, fr. It.
   architrave; pref. archi- + trave beam, L. trabs.] (Arch.)
   (a) The lower division of an entablature, or that part which
       rests immediately on the column, esp. in classical
       architecture. See {Column}.
   (b) The group of moldings, or other architectural member,
       above and on both sides of a door or other opening,
       especially if square in form.

Source : WordNet®

architrave
     n 1: the molding around a door or window
     2: the lowest part of an entablature; rests immediately on the
        capitals of the columns