The electronic mail contact and maintenance person at a site connected to the Internet or UUCPNET. Often, but not always, the same as the admin. The Internet standard for electronic mail (RFC 822) requires each machine to have a "postmaster" address; usually it is aliased to this person. See also webmaster.
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Nearby terms: POSTGRES « PostgreSQL « posting « postmaster » post office problem » Post Office Protocol » post-order traversal