noun the center of the volta, ring, or manege ground, around which a horse turns.
2. pillar ·adj having a support in the form of a pillar, instead of legs; as, a pillar drill.
3. pillar ·noun a portable ornamental column, formerly carried before a cardinal, as emblematic of his support to the church.
4. pillar ·noun 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.
5. pillar ·noun 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.