Nordrassil prior to Archimonde's ascent
World Tree refers to two great trees in Azeroth:
- Nordrassil, the original World Tree blessed by the dragon aspects, and
- Teldrassil, the tree created by the night elves in a failed attempt to restore their immortality.
There is another possible World Tree shown in a piece of concept art titled Idrassil, found in The Art of World of Warcraft. However, it is probably just an early version of Teldrassil.
In the Grizzly Hills in Northrend is a city of Furbolg called Grizzlemaw. This could be a failled attempt of making another World Tree.
The idea of a World Tree is almost certainly a reference to the World Tree of Norse mythology, Yggdrasil. Their names are similar, they both have wells underneath them: the Well of Eternity beneath Nordrassil, and the Well of Urd beneath one of the roots of Yggdrasil. Also, a dragon, Nidhoggr gnawed at the roots of Yggdrasil, which could reference back to either Deathwing or Archimonde. These parallels only apply to Nordrassil, the "true" World Tree, and not Teldrassil, the "false" one.