While its exact origins are unclear and debated, its meaning is generally understood to be an intensifier, similar to saying "very" or "extremely". It can be used to express:
* High intensity or quantity: "I was up whazoo tired after that workout."
* Excitement or enthusiasm: "The party was up whazoo crazy!"
* A large amount of something: "He's got a whole whazoo of money."
The term might have evolved from the phrase "up to one's wazoo," implying being full to the brim with something. The word "wazoo," in turn, seems to have been derived from the word "washtub," possibly due to its association with abundance.
It's important to remember that while the phrase "up whazoo" is considered informal and can be humorous, it might not be appropriate in all contexts. It's also worth noting that the term can sometimes be used in a derogatory or offensive way, depending on the intention and context.