- Proper noun. A 64-mile Interstate freeway surrounding Washington, D.C..
- Proper noun. (context, mostly local usage) Certain expressways that surround cities.
- Proper noun. (US, politics) The US federal government and policy and lobbying organizations, located in Washington, D.C..
- Proper noun. (rfv-sense) Washington D.C..
- Adjective. Of or relating to the culture of Washington, D.C.; politicized.
- Noun. (US) A freeway that encircles a city.