- Refers to the context of or associated specifically with the modern political entity of the United States of America.
- Structures, generally enclosed, that are used or intended to be used for sheltering an activity or occupancy.
- Barriers that swing, slide, tilt, or fold to close a doorway, usually of solid and finished construction and usually leading to or separating interior spaces. Use also for similar features that close a container or a piece of case furniture. For barriers of less solid or finished construction, and usually separating two exterior spaces, use "gates."