What does Nym Server mean?
A nym server is a pseudonym server that furnishes an untraceable email address. The purpose of this server is to allow users to have usernames (pseudonyms) and send and receive messages without revealing their true identities.
Even the nym server operators cannot trace a user's email address.
Techopedia explains Nym Server
Users find nym servers over the Internet and must subscribe to them in order to use them. Nym servers send the pseudonymous emails and forward replies to the user’s real email address. In addition to the nym server, a network of anonymous remailers is also involved in routing the emails.
To develop a nym, a pretty good privacy key pair must be created and sent to the nym server, along with a reply block for anonymous remailers, which includes instructions on sending a message to the creator’s real email address. By way of the reply block, a confirmation message is sent through the nym server. The reply block permits the user to use the nym server account for two-way mailing.
When a nym server system is properly developed, the chances of tracing the nym server, or identifying the real email sender, are slim to none. This makes it difficult to punish or catch senders who sign up with nym servers and use them for malicious purposes.