Relating to the collection, sorting and delivery of mail.
"The postal worker arrived early to sort the pile of letters before heading out for deliveries."
In plain English: Postal means anything related to sending and receiving mail through the post office.
"The postal worker delivered the letter to my front door."
Usage: Use "postal" to describe anything related to the system of sending letters and packages, such as a postal code or postal worker. Avoid using it interchangeably with "post," which functions primarily as a noun referring to the mail itself or an action like posting a notice.
Postal comes from combining the word post with the suffix -al, following the pattern of the French term postal. It entered English to describe anything related to sending letters or packages via the mail system.