Woo-hoo! is a catchphrase used by Homer. He uses it when he is happy. It is often followed by a D'oh!. In one episode, he is seen going, "D'oh! D'oh! D'oh! Woo-Hoo! D'oh! D'oh! D'oh! D'oh! D'oh! D'oh! Woo-Hoo!" This is while a roulette wheel is spinning around. When it gets to 17, his number, he says, "Woo-Hoo!" In another, he says it, but when Marge protests, he says, "I said, 'Woo-Hoo,'" in the same tone. In Mona Leaves-a, Mona says in her will that she will give Homer the best thing. He said Woo-Hoo.

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