pillar

Short definition from Wiktionary

Noun

1. 1
   A large post, often used as supporting architecture.
2. 2
   Something resembling such a structure.
3. 3
   An essential part of something that provides support.
4. 4
   A portable ornamental column, formerly carried before a cardinal, as emblematic of his support to the church.
5. 5
   The centre of the volta, ring, or manege ground, around which a horse turns.
6. 6
   The body from the hips over the core to the shoulders.
7. 7
   A vertical, often spire-shaped, natural rock formation.

Verb

1. 1
   To provide with pillars or added strength as if from pillars.

Proper noun

1. 1
   A surname.