meaning of priority mail refers to a service offered by USPS for fast delivery of packages and mail within the U.S. and internationally. Priority Mail typically takes 1-3 business days for domestic shipments and includes benefits such as tracking, delivery confirmation, and up to $100 of insurance for eligible items. Priority Mail is a popular choice for businesses and individuals who need a quicker shipping option compared to standard mail services, and it is more affordable than expedited services like Priority Mail Express.