Picture a hollow about the size and shape of a cooking pot sunk into a flat surface. The surface is meant to be level, and here it is not: something has gone down into it. Whether the hollow was rubbed away over years or cut on purpose, the picture is the same — a pot-shaped gap where flat ground should be.
可以想成一個大小、形狀都像鍋子的凹處陷在一片平面裡。那個平面本來應該是平的，偏偏這裡凹下去了。至於這個凹處是被磨了好幾年磨出來的，還是特地開出來的，畫面其實一樣：平面上出現一個鍋子形狀的缺口。pothole 的幾個用法，都是這個畫面換一個地點——馬路、河床、地底、爐台。
From the word’s history
The evidence records the road and cave senses as dialect pot (a pit or hollow) plus hole, with the cave sense attested from at least 1809; it records the stove sense separately as pot (a cooking pot) plus hole, attested from at least 1811.
來源把這個字記成兩條路線：路面和洞穴那一支是方言的 pot（坑、凹洞）加 hole，洞穴義至少可追到 1809 年；爐子那一支則記成 pot（鍋子）加 hole，至少可追到 1811 年。也就是說「鍋子形狀」這個畫面好用，但不是同一個歷史來源。
Wiktionary, "pothole" (etymology 1)
登入就可以看每一支怎麼連回核心畫面。