zip code

US: (zip′kōd′)

Inflections of 'zip code' (v): (⇒ conjugate)

zip-codes

v 3rd person singular

zip-coding

v pres p

zip-coded

v past

zip-coded

v past p

WordReference Random House Unabridged Dictionary of American English © 2026

zip′ code′, 

1. Stamps 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.

Also, ZIP′ code′, Zip′ code′. 

• Z(one) I(mprovement) P(rogram) 1960–65, American.

zip-code  (zip′kōd′), v.t., -cod•ed, -cod•ing. 

1. Stamps to provide or mark with a zip code:
   Zip-code all mail.

Also, ZIP′-code′, Zip′-code′. 

Collins Concise English Dictionary © HarperCollins Publishers::

zip code noun

1. the US equivalent of postcode

Etymology: 20th Century: from z(one) i(mprovement) p(lan)

WordReference Random House Learner's Dictionary of American English © 2026

ˈZIP ˌcode, n. [countable]

1. Stamps a numerical code of five or nine digits written or printed directly after the address on a piece of mail to specify the addressee's postal delivery area in the U.S.