Here are some other terms you might encounter:
* Stair post: This is a general term that refers to any post that supports a railing on a staircase.
* Handrail post: This emphasizes the post's role in supporting the handrail.
* Baluster post: This is used when the post is specifically designed to support balusters, the vertical spindles that make up the railing.
The term "bannister post" is not as common, but it is understandable. "Bannister" and "handrail" are often used interchangeably, so it makes sense to call a post that supports a bannister a "bannister post."