pillar

noun

1. a fundamental principle or practice"science eroded the pillars of superstition"
2. anything that approximates the shape of a column or tower"the test tube held a column of white powder"
3. a prominent supporter"he is a pillar of the community"
4. a vertical cylindrical structure standing alone and not supporting anything (such as a monument)
5. (architecture) a tall vertical cylindrical structure standing upright and used to support a structure