Capital
Doric Order capitals are easily distinguished from those of the Ionic and Corinthian Orders by their simplicity. There are no scrolls, no frilly botanical forms; just a disc supporting a slab of stone.
The Doric capital consists of three parts, starting from the bottom and working up. First is the neck, a fluted ring that serves as the transition from column to capital. Next comes a convex disc called an echinus because of its resemblance to the shell of a sea urchin (echinus in ancient Greek). The square slab above the echinus is the abacus, which joins the capital to the architrave and helps distribute the weight of the entablature over the columns.
The profile of the Doric echinus became straighter over time, gradually losing its resemblance to the sea urchin for which it was named.