Yggdrasill

Giant ash tree springing from body of Ymir and supporting universe; its roots extended to Asgard, Jotunnheim, and Niffheim.
Found on http://www.factmonster.com/ipka/A0197623.html

Yggdrasill

in Norse mythology, the world tree, a giant ash supporting the universe. One of its roots extended into Niflheim, the underworld; another into ... [5 related articles]
Found on http://www.britannica.com/eb/a-z/y/8

Yggdrasill

Yggdrasill (ig'drusil, yOOg'–) , in Norse mythology, the great tree of the world. Its branches and roots extended through all the universe—the heavens, the earth, and the underworld. At its top sat an eagle, at its bottom twined a serpent, and between them ran a squirrel breeding...
Found on http://www.infoplease.com/ce6/ent/A0853075.html
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