The red supergiant star in the constellation of Orion.
This ageing beauty is one of the few stars on which surface features have been observed.
Pronounced "beetlejuice", the word was thus misspelt to provide the name of the titular villain in a 1980's Tim Burton film.
Geek#1: Someday our sun will run out of hydrogen fuel and become a giant like Betelgeuse.

Geek#2: Someday you'll regret wasting your life on the internet, when your eyes are burnt out from the persistant glare of LCD screens.
by Uncle Jimbo September 30, 2006
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