# moulin

/muˈɫæn/ (US) · /mˈuːlɪn/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/moulin
Updated: 2026-05-30

## Definition

a small, deep hole in the ground that is often filled with water. It is usually found in soft rock like limestone and can be dangerous because the sides are steep and slippery.

For teachers: a small, deep, cylindrical hole in the ground, typically found in limestone or other soluble rock. Often contains water and is formed by the collapse of a cave roof or the erosion of a sinkhole.

## Examples

- The hikers were warned to stay away from the moulin in the limestone field.
- After the heavy rains, the moulin filled with water and became a deep blue pool that looked like a well.
- The landscape was dotted with numerous moulins, their steep walls providing a stark contrast to the surrounding flat grasslands and serving as a reminder of the region's extensive subterranean drainage system.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.