Roche Moutonnée, Wales

The typical roche moutonnée is a small rocky landform, oriented in the direction the glacier flowed. The upstream or stoss side is gently sloping and smooth, and the downstream or lee side is steep and rough. That is generally the opposite of how a drumlin (a similar but larger body of sediment) is shaped. This example is in Cadair Idris Valley, Wales.

Many glacial features were first described in the Alps by French- and German-speaking scientists. Horace Benedict de Saussure first used the word moutonnée ("fleecy") in 1776 to describe a large set of knobs of rounded bedrock. (Saussure also named seracs.) Today a roche moutonnée is widely believed to mean a rock knob that resembles a grazing sheep (mouton), but that isn't really true. "Roche moutonnée" is simply a technical name nowadays, and it's better not to make assumptions based on the etymology of the word. Also, the term is often applied to large bedrock hills that have a streamlined shape, but it should be restricted to landforms that owe their primary shape to glacial action, not preexisting hills that were merely polished by it.