Also found in: Dictionary, Thesaurus, Medical.
spam relaySending mail to a destination via a third-party mail server or proxy server in order to hide the address of the source of the mail. When email servers (SMTP servers) are used, it is known as an "open relay" or "SMTP relay," and this method was commonly used by spammers in the past when SMTP servers were not locked down. Today, most spam relay is provided by proxy servers and botnets. See spam, spam filter, botnet, open proxy server and MAPS.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.