Meaning

• 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.

Meaning

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

• To corner somebody for an unexpected interview.