Tangentially is the adverb of tangential: it means only at the edge, in a side way, not in the way that really counts. In practice you meet it in two shapes.

Tangentially這個字 is the adverb of tangential是tangential的副詞，it means意思是 only at the edge, in a side way只沾到邊、順帶一下，not in the way that really counts不是真正重要的那種方式。In practice實際上 you meet it你會看到它 in two shapes有兩種用法。

Most often it sits with 'related', 'connected', or 'linked': 'the two cases are only tangentially related', 'he was tangentially involved in the scandal'. Almost always there is an 'only' or 'at most' nearby, because the whole job of the word is to shrink a connection down — to admit it exists while saying it is thin.

Most often最常 it sits with 'related', 'connected', or 'linked'它會搭配'related'、'connected'或'linked'這些字：'the two cases are only tangentially related'像'the two cases are only tangentially related'（這兩個案子只有間接關係）、'he was tangentially involved in the scandal'或'he was tangentially involved in the scandal'（他跟這醜聞只有間接牽連）。Almost always幾乎都 there is an 'only' or 'at most' nearby會有'only'或'at most'在旁邊，because因為 the whole job of the word is to shrink a connection down這個字的作用就是把一段關聯縮小——to admit it exists while saying it is thin承認它存在，同時說它很薄弱。

The second shape is about how someone speaks or writes: 'she mentioned it tangentially' means she brought it up in passing, off to the side of her main point, not head-on.

The second shape第二種用法 is about how someone speaks or writes是關於一個人說話或寫作的方式：'she mentioned it tangentially'像'she mentioned it tangentially'這句 means意思是 she brought it up in passing她是順帶提到這件事，off to the side of her main point放在她主要重點的旁邊，not head-on不是正面去談。

This is a formal word, at home in reports, journalism, and academic writing; in conversation people say 'sort of related' or 'in a roundabout way'.

This is a formal word這是個正式用字，at home in reports, journalism, and academic writing常出現在報告、新聞和學術寫作裡；in conversation口語裡 people say 'sort of related' or 'in a roundabout way'大家會說'sort of related'或'in a roundabout way'。

It also has a plain physical meaning in science: moving or acting along a tangent, at right angles to the line from the centre — 'the fragment flew off tangentially'. That literal picture is the source of everything else: a line that meets a circle at one point and then leaves in its own direction.

It also has a plain physical meaning in science它在科學裡也有一個很直白的物理意思：moving or acting along a tangent沿著切線方向移動或作用，at right angles to the line from the centre跟圓心拉出的那條線垂直——'the fragment flew off tangentially'像'the fragment flew off tangentially'（碎片沿切線方向飛出去）。That literal picture這個字面的畫面 is the source of everything else就是其他所有意思的來源：a line that meets a circle at one point and then leaves in its own direction一條線碰到圓的一點，然後就往自己的方向離開。