Hooroo is a distinctively
Australian way of saying “goodbye”.
The "truly wondrous fantasmagorically splendiferously magickal word hooroo" (credited to someone's Uncle Wally) echoes two likely sources.
It's a bit of a joyous exclamation, as in "Hooroo! hooroo!
hooray!" (Darby O'Gill), and it's also something of an owl's
hoot, as in "the proper hooroo, hooroo" (The Sword in the
Stone).
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"For my part, I do believe I should go quite
insane, were I to live in {a} Land where
people wandered around screaming, 'HOOROO' at
one- another". said Werewolfy"
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