In many muds, in order to select the second one of something that shares the same keyword, you identify it as 2.something.
A result of this was that many people began using it in ordinary speech. For instance, if I were to accuse Bob of being like
Jim, I might say Bob is 2.Jim. Sometimes people in muds would have different characters. For instance Jim might have the character
Jimbob, so it could be said Jimbob was 2.Jim.
When using this terminology, you are usually trying to convey a sense of similarity.
For instance, if you said that this was a 5.Shanoyu rant
, you might be impling that all of Shanoyu's rants are the same.
You might just be saying that it is the 5th rant chronologically that Shanoyu has written.