- a system used in the U.S. to facilitate the delivery of mail, consisting of a five- or nine-digit code printed directly after the address, the first five digits (initial code ) indicating the state and post office or postal zone, the last four (expanded code ) the box section or number, portion of a rural route, building, or other specific delivery location.
- to provide or mark with a zip code: Zip-code all mail.
- the US equivalent of postcode
