I'm defining "address" as "a physical location, usually visibly numbered". Numbered was used in the definition to exclude purely geographical features not usually considered to have or need an address. Visibly was used in the definition to exclude entities that might be numerically coded (like census features) but the number is not typically apparent nor used for directional or delivery purposes. Usually was used in the definition because exceptions abound (such residences in Carmel).

Enumerating the possible kinds of addresses resulted in:

• buildings.
• entire floors of buildings.
• apartments/offices/rooms in buildings.
• cubicles/mailstops in buildings.
• loading docks.
• slips on boat docks.
• slots in trailer parks.
• post office boxes and private mail drops.
• military APO/FPO addresses.
• jail/prison cells.
• campground lots.
• outbuildings (not usually visibly numbered, but often desireable in delivery databases).
• undeveloped parcels (not usually visibly numbered, but often required in address databases).

What other kinds of "physical locations, usually visibly numbered" have I forgotten to include in the above list? Two questionables are:

• hospital beds.
• cemetary plots.