1.A public box for deposit of mail, where it is later picked up by the postal authority for delivery.
2.A private box to recieve delivery of mail. The term is used both for boxes receiving mail delivered by the public postal authority, or by a private services, such as for mail to employees in large corporations.
3.(Computers) A location within a computer storage device where electronic mail is held until it is retrieved by the addressee. Creation and use of an electronic mailbox requires special software as well as a data storage device.
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