A politburo is the small, most powerful committee at the top of a Communist party — the group that really decides.

A politburo is the small, most powerful committee at the top of a Communist partypolitburo是共產黨內部最上層、最有權力的一個小委員會——the group that really decides真正做決定的那群人。

The Soviet Union had one. China has one. Other Communist parties copied both the name and the idea: a tight circle above even the larger central committee.

The Soviet Union had one蘇聯有過一個。China has one中國也有一個。Other Communist parties copied both the name and the idea其他共產黨也把這個名字和概念一起沿用：a tight circle above even the larger central committee一個比更龐大的中央委員會還要更小、更核心的圈子。

Though actually, the word is Russian: it is a short form of “political bureau.” English kept the foreign title, the way we keep “cabinet” or “senate,” rather than translating it every time. In Taiwan, news about China says 政治局; English news usually keeps Politburo, often with a capital P when it means that specific body.

Though actually, the word is Russian不過其實，這個字源自俄文：it is a short form of "political bureau."是「political bureau」的簡稱。English kept the foreign title英文保留了這個外來的稱呼, the way we keep "cabinet" or "senate,"就像我們保留cabinet或senate一樣，rather than translating it every time而不是每次都翻譯它。In Taiwan, news about China says 政治局在台灣，關於中國的新聞會說「政治局」；English news usually keeps Politburo英文新聞通常保留Politburo這個字, often with a capital P when it means that specific body在指那個特定機構時常常大寫P。

It is a formal word of political history. You do not use it for a company’s board or a school committee, even if those groups also decide things.

It is a formal word of political history這是個政治史上的正式用語。You do not use it for a company's board or a school committee你不會用它來講公司的董事會或學校的委員會，even if those groups also decide things即使那些團體也在做決策。

People outside those systems sometimes use it jokingly for any small group that secretly runs things. That is a stretch, and it can sound mocking.

People outside those systems sometimes use it jokingly for any small group that secretly runs things在那些體制之外，有人有時候會開玩笑地用它來稱呼任何暗中掌控一切的小團體。That is a stretch, and it can sound mocking這是一種引申用法，聽起來可能帶點嘲諷。