| 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. |
[zip-kohd] 
| to provide or mark with a zip code: Zip-code all mail. |
| Zip Code A trademark used for a system designed to expedite the sorting and delivery of mail by assigning a series of numbers to each delivery area in the United States. |