in the classical orders, this describes columns rather thickly set, with an intercolumniation to which two diameters are assigned.[51]
having columns separated by a distance of twice their thickness
• (n.) A systyle temple or other edifice. • (a.) Having a space equal to two diameters or four modules between two columns; -- said of a portico or building. See Intercolumniation.
Sys'tyle adjective [ Latin systylos , Greek 
In Grecian and Roman architecture, a structure is described as systyle if it has a space equal to two diameters or four modules between two columns.
having an intercolumniation of two diameters. See illus. under