Well, there are actually three words to go with the word of the week: Doric, Ionic, and Corinthian. According to the Builder’s Comprehensive Dictionary (Robert Putnam, Reston Pub. Co., c1984), “order” refers to the three types of Greek columns.
See figure one (courtesy of thinkquest.org). Doric is the least frilly column. Notice how it is wider at the bottom than the top. This gives the illusion the column is taller. The Ionic column has the recognizable “cinnamon roll” or volute design while the Corinthian has the acanthus (flower leaves) at the top.
Here is a bonus word for the week: “entasis”. The columns have a slight bulge, or entasis, in them to help give the appearance of looking straight. There is such an obsession with perfection in these designs the columns are made slightly warped to counter-act our own eyes’ perception! Entasis has also been used in double-jamb doorways to create the same effect.
http://library.thinkquest.org/11114/pictures/greek1.gif