An outside step leading up to the door of a building, usually a home.

“On one's doorstep.”

One's immediate neighbourhood or locality.

“They want to build the prison right on our doorstep; it will only be half a mile away and being that close scares me.”

A big slice, especially of bread.

To visit one household after another to solicit sales, charitable donations, political support, etc.

To corner somebody for an unexpected interview.