打轉的那一團（名詞）／正在打轉（動詞）
兩個詞性共用同一個畫面，只是站的角度不同：名詞看的是那一團東西，動詞看的是它的動作。
noun · C1
A small turning patch of water, air, smoke, or dust. It spins round in one spot, or runs back the other way, while the main flow keeps going past it.
渦流
核心畫面
One way to hold this word: a stream runs past a rock, and just behind the rock the water cannot go straight. It curls back and turns in a small circle at the edge of the flow. That little turning patch is the whole word — as a noun it is the patch, as a verb it is what the water is doing.
eddy 可以想成這個畫面：溪水流過一塊大石頭，石頭後面的水沒辦法直直往前，於是捲回來，在主流旁邊繞起小圈。那一小團…更多收起
eddy 可以想成這個畫面：溪水流過一塊大石頭，石頭後面的水沒辦法直直往前，於是捲回來，在主流旁邊繞起小圈。那一小團打轉的東西就是這個字的全部。當名詞時，它是那一團；當動詞時，它是那一團正在做的事。水、風、煙、灰塵都可以這樣繞，差別只在材料，不在畫面。From the word’s history
Wiktionary traces eddy to Old English edea, from ed- (turning, back, reverse) plus ea (water) — literally water that turns back. That is the same picture the modern word carries.
根據 Wiktionary，eddy 來自古英文 edēa，是 ed-（回轉、往回）加上 ēa（水），字面就是「往回走的水」。今天這個字用的還是同一個畫面。
Wiktionary (kaikki:3f6f69a190036ae4:615949688): From Middle English eddy, from Old English edēa, from ed- ("turning, back, reverse") + ēa ("water").
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