Entasis is a slight thickening in the central part of the shaft of a column in order to correct the optical illusion that the rectilinear sides give, of an inward curve.
The architrave of the jonic order is composed of three strips, each slightly more prominent than the lower one. The frieze is continuous around the entire temple and is usually ornamented with sculptural decoration. On the facade, the columns are more slender than the Doric ones, have a much smaller entasis, and are placed at a greater distance from each other.
