A pillar, like a column (see above), is a vertical architectural support, but it is usually rectangular in plan. Occasionally it may be octagonal, cruciform, or T-shaped. In traditional architecture, pillars are built of individual stones or bricks, not drums or an entire shaft. Because a pillar is heavier than a column (shorter in proportion to its cross-section), it can carry loads with a diagonal thrust. It is thus a support for wide, heavy arches. Particularly stout pillars, such as those under bridges, are called piers.
A pillar may have a base, shaft, and impost capital, but as a rule these elements are more simply shaped than those of a column, and the base or impost capital may be missing in purely utilitarian pillars, such as those of a cistern.
Pillars that have been adorned at the corners with engaged half- or three-quarter columns are called cantoned pillars. They were freely employed in the hermitages of Kellia in particular, since such corner columns could very easily be carved out of the corners of the brick pillars.
- Orlandos, A. K. Basilik», pp. 356-58. Athens, 1952.