In a printed document:
* Section: A distinct part of a text or page.
* Vertical line: A vertical line that separates text or numbers.
* Line: A single row of text.
* Article: A piece of writing in a newspaper or magazine.
In architecture:
* Pillar: A vertical structural support.
* Post: A vertical support, often made of wood.
* Shaft: The main vertical part of a column.
In a data table:
* Field: A single piece of data in a table.
* Attribute: A characteristic of a data entry.
Other:
* Line: A straight line of objects or people.
* File: A series of files or folders arranged in a vertical stack.
* Formation: A group of people or things arranged in a straight line.
To give you the best synonym, please provide me with the context in which you're using the word "column."