www.alphadictionary.com

Hooray is an exclamation used to express joy or approval, except in New Zealand, where it means "goodbye" (go figure).

It is said to be a late 19th century variant of hurrah, itself formed in the late 17th century as a variant of huzzah, which is speculated to be used originally as a sailor's cry when hauling. Its history before that is obscured by the fog of time.

Would people agree that hoo-rah is often used sarcastically? As in, "What's the big hoo-rah?"

I note also that American English once had hurra's nest, meaning a state of confusion. Has anyone ever come across this? I sure haven't.

My mother invariably described my room as a hurrah's nest. Merriam-Webster provides a context that makes sense:

a tangle of debris blocking a trail or stream