pothole (n.)

also pot-hole, "more or less cylindrical cavity from a few inches to several feet deep in rock," 1826, originally a geological feature in glaciers and gravel beds, from Middle English pot "a pit, a hollow, a deep hole for a mine or from peat-digging" (mid-15c.; 12c. in place-names), now generally obsolete in those senses, but preserved in Scotland and northern England dialect; perhaps ultimately from or related (via a Scandinavian source) to pot (n.1) on notion of "deep, cylindrical shape." Applied to a hole in a road from 1909.