capital

In architecture, a stone placed on the top of a column, pier, or pilaster, and usually wider on the upper surface than the diameter of the supporting shaft. It comes directly below the entablature (architrave, frieze, and cornice) and/or the lintel (top of a door or window frame). A capital consists of three parts: the top member, called the abacus, a block that acts as the supporting surface to the superstructure; the middle portion, known as the bell or echinus; and the lower part, called the necking or astragal.

There are three basic types of capital, each originating with the ancient Greeks: the Doric; the Ionic, which is a scroll-like design; and the Corinthian, which is very ornate in style.