Source : Webster's Revised Unabridged Dictionary (1913)

Plinth \Plinth\, n. [L. plinthus, Gr. ? a brick or tile, a
   plinth, perh. akin to E. flint: cf. F. plinthe.] (Arch.)
   In classical architecture, a vertically faced member
   immediately below the circular base of a column; also, the
   lowest member of a pedestal; hence, in general, the lowest
   member of a base; a sub-base; a block upon which the moldings
   of an architrave or trim are stopped at the bottom. See
   Illust. of {Column}.

Source : WordNet®

plinth
     n : an architectural support or base (as for a column or statue)
         [syn: {pedestal}, {footstall}]