pillar

noun

1. 1

   (architecture) a tall vertical cylindrical structure standing upright and used to support a structure

2. 2

   a vertical cylindrical structure standing alone and not supporting anything (such as a monument)

3. 3

   a fundamental principle or practice

   science eroded the pillars of superstition

4. 4

   a prominent supporter

   he is a pillar of the community

5. 5

   anything that approximates the shape of a column or tower

   the test tube held a column of white powder

   a tower of dust rose above the horizon