What is the more widely used alternative term for deferred messages?

The term "greylisted" is widely used in the context of email security, particularly with regard to spam filtering and mail delivery. When a message is greylisted, it means that the email has been temporarily rejected and will be tried again later. This process is a tactic used to minimize spam; legitimate senders, which typically have configured retry mechanisms in their mail servers, will attempt to resend the message after a delay, while many spammers do not retry, thus reducing the amount of unwanted mail that reaches the recipient's inbox.

In contrast, terms like “delayed messages” or “suspended messages” may imply a broader range of situations where messages are simply held up for various reasons, but they do not specifically convey the method of handling that greylisting entails. “Pending messages” might suggest that messages await further processing but lack the specific relationship to the greylisting technique.

Therefore, "greylisted" is the term that most accurately and widely reflects the specific practice of delaying email delivery as a spam prevention measure.