plinth

A block or slab on which a pedestal, column, or statue is placed.

The base block at the intersection of the baseboard and the vertical trim around an opening.

A continuous course of stones supporting a wall.

A square base, as for a vase.

In architecture, the flat square table or slab under the molding of the base of a Roman or Renaissance column, of which it constitutes the foundation, and the bottom of the order; also, an abacus; also, a square molding or table at the base of any architectural part or member, or of a pedestal, etc. See phrases below, and cuts under base, column, and capital.