Noun
a drop where mail can be deposited
Source: WordNetPOP supports simple download-and-delete requirements for access to remote mailboxes (termed maildrop in the POP RFC's). citation IMAP email servers The Internet Message Access Protocol (IMAP) provides features to manage a mailbox from multiple devices. Source: Internet
This unique identifier is permanent and unique to the maildrop and allows a client to access the same message in different POP sessions. Source: Internet