Think of a knot on a smooth line. Somewhere along a cord that should run evenly, material gathers and the line swells into a small round rise. That is the one picture this word keeps: a swelling where something has collected. On a in the wrist, what collects is fluid, and you can see and press the lump. On a nerve, what collects is cell bodies, and the swelling becomes a junction where signals meet before travelling on. From there writers borrow the knot once more, for any place where everything in a city or a trade ties together.
The source records the word as borrowed from Ancient Greek ganglion, glossed as an encysted tumour on a tendon or aponeurosis.
來源記錄它借自古希臘文 γαγγλίον，而希臘文的解釋是「長在肌腱或腱膜上的囊腫」。也就是說，手腕上那顆包才是這個字最早在講的東西。神經上的那一團細胞為什麼共用同一個名字，來源沒有說明；把它們連在一起的「結」是我們給學習者的教學畫面，不是在主張歷史上的先後。
Wiktionary entry supplied in packet (kaikki:3f6f69a190036ae4:926041324)
Two branches
身體上鼓起來的一團
這一組是實體的結：東西聚在某一點，把表面撐起來。差別只在聚的是液體還是細胞。
noun · C1
A soft lump filled with liquid that grows from the covering of a tendon or from a joint, most often on the back of the wrist. It is harmless, but it can be painful, and it is often called a ganglion cyst.
腱鞘囊腫（手腕上的水瘤）
借出去的比喻：匯集的中樞
把神經節「訊號在此交會、再送出去」的畫面整個搬到身體外面：港口、市集、圖書館都可以是那個結。
noun · C2
A place where a great deal of activity, thought, trade, or power comes together, described as if it were a nerve centre. The source marks this as a transferred use, and it belongs to formal or literary writing rather than everyday speech.
（比喻）中樞、匯集點