n. | 1. | The general and popular term for a firm, upright, insulated support for a superstructure; a pier, column, or post; also, a column or shaft not supporting a superstructure, as one erected for a monument or an ornament. |
| 2. | Figuratively, that which resembles such a pillar in appearance, character, or office; a supporter or mainstay; as, the Pillars of Hercules; a pillar of the state. |
| 3. | (R. C. Ch.) A portable ornamental column, formerly carried before a cardinal, as emblematic of his support to the church. |
| 4. | (Man.) The center of the volta, ring, or manege ground, around which a horse turns. |
a. | 1. | (Mach.) Having a support in the form of a pillar, instead of legs; as, a pillar drill. |