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initial code

noun
1.
See under zip code.

zip code

noun
1.
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.
Origin
1960-1965
1960-65, Americanism; Z(one) I(mprovement) P(rogram)
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for initial-code

zip code

noun
1.
the US equivalent of postcode
Word Origin
C20: from z(one) i(mprovement) p(lan)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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7
9
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