If you really want a straight answer, ask Diaglo. He uses the terms the most often. I'm fairly sure that these are just mixes of 3e and 2e (2000 ed), and 3e and 3.5e (3.11).
I kinda want this to spiral OT into the hive though...
We penguins find this analogy insulting. We'd prefer that 3.0e were refered to as "Slackware Kernel 1.2.13", and that 3.5e take "Debian 3.0r2" as its moniker.
Some of us (me included? who knows.) find it to be like a joke that was kinda humorous long long ago, but has ceased to be so because the guy that told it the first time keeps telling it over and over.