Eddy
A tsunami hits a roof and then corrects itself. This causes it to swirl around, creating an eddy.
An eddy requires water to change direction and then twirl around, and when the tsunami hits the roof, that's exactly what it does.
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よど
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There is a person trying to create an eddy with a tsunami, and when their roof correction device is shown to be effective, they sing: "This is how you do (よど) it."
Imagine them singing this, emphasizing the "you do" part of the song as they watch the eddy being formed.