政治上的第二階：任命出來的官員
這兩個用法都是照字面走：頂端下面那一格，而且是被任命的政治職位。差別只在美國和英國把這一格放在哪裡。
noun · C1
In the United States, a very senior official in a government department who is one level below the secretary, the person in charge of the whole department.
次長
核心畫面
One way to hold this word: draw the chart of a government department. At the top there is one box, and the person in it is called the secretary — in a government that title means the head of the whole department, not an office worker. `Under-` simply moves you one box down. That is the entire word: the rank directly beneath the top. It says nothing about what the person does all day, which is why the same title can belong to a politician in one country and to the official who runs the building in another. Find the top box first, and the word tells you where to stand.
可以想成：先畫一張部門的組織表。最上面那一格是 secretary——在政府裡，這個字指的是「部門首長」，不是辦公室…更多收起
可以想成：先畫一張部門的組織表。最上面那一格是 secretary——在政府裡，這個字指的是「部門首長」，不是辦公室秘書。under- 的作用只是把你往下挪一格。整個字就是這樣：頂端下面那一階。它沒有說這個人整天在做什麼，所以同一個職稱在不同國家可以是政治人物，也可以是管整棟樓運作的事務官。先找到最上面那一格，這個字就會告訴你站在哪裡。From the word’s history
Wiktionary gives the word simply as under- + secretary. Nothing is hidden inside it: the prefix marks rank and the noun names the post it is measured against, which is why every meaning has to be read against whoever the local secretary is.
Wiktionary 直接記載這個字就是 under- 加 secretary。裡面沒有藏東西：字首標的是位階，後面的名詞標的是用來對照的那個職位。所以每一個用法都得先看當地的 secretary 是誰，才讀得出這個人有多大。
Wiktionary entry `undersecretary` (noun), etymology text supplied in evidence packet: From under- + secretary.
Two branches
讓部門轉得動的人：事務主管
位置還是同一格，內容卻換了：這一格裝的不是政治人物，而是管日常運作的事務官。
noun · C1
In Britain, a senior government official who is in charge of the everyday running of a department.
常務次長