The National Diet is the highest State power of which country?

Player #7850667, it isn't a Japanese word. In political terms a diet is a formal parliamentary assembly. The word is used in Europe as well. The name derives from Latin diaeta which might have come from ancient Greek for arbitration.

The word diet derives from Latin and was a common name for an assembly in medieval European polities like the Holy Roman Empire. The Meiji Constitution was largely based on the form of constitutional monarchy found in nineteenth century Prussia that placed the king not as a servant of the state but rather the sole holder of power and sovereignty over his kingdom, which the Japanese view of their emperor and his role at the time favoured. The new Diet was modeled partly on the German Reichstag and partly on the British Westminster system. Unlike the post-war constitution, the Meiji constitution granted a real political role to the Emperor, although in practice the Emperor's powers were largely directed by a group of oligarchs called the genrō or elder statesmen.

where did the word "Diet" in Japanese come from? please be thorough.

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