Origin: Latin prefix post-
Postcode has 3 different meanings across 1 category:
a code of letters and digits added to a postal address to aid in the sorting of mail
"The courier used his postcode to ensure the package was sorted correctly before delivery."
A sequence of letters and numbers added to a postal address to aid the sorting and delivery of post or mail.
"The driver used my postcode to ensure his package was sorted correctly and delivered straight to my door."
In plain English: A postcode is a short code used to identify a specific area for mail delivery.
"Please write your full address and postcode on this form so we can deliver your package correctly."
Usage: Use this word as an uncountable noun when referring generally to the system, but use it in singular form for specific codes like "What is your postcode?" Avoid using the verb form unless you are specifically describing the act of assigning or marking that code onto something.
To give a postcode to; to mark with a postcode.
"The clerk asked me to write my postcode on every envelope before mailing them."
In plain English: To postcode something means to send it by mail using its postal code address.
"I need to postcode this letter immediately so it arrives in time for Christmas."
The word postcode is a straightforward combination of the words post and code that describes a system for sorting mail by location. It entered English as a practical term to replace longer address formats with concise numerical or alphanumeric identifiers.