Abbreviation: "Realtime Blackhole List". A service that allows people
to blacklist sites for emitting {spam}, and makes the blacklist
available in real time to electronic-mail transport programs that
know how to use RBL so they can filter out mail from those sites.
Drastic (and controversial) but effective. There is an RBL home page.
[glossary]
[Reference(s) to this entry by made by: {black hole}]