A deep gorge; a gully.

a steep snow- or ice-filled gully on a mountainside.

a long, steep gully cutting up the face of a mountain

Often steep, narrow chutes usually banded by cliffs. Syn: Chute, Gully

a steep chute, which may have snow or ice.

a snow or ice filled gully often provides the best or only route up a mountain face

more info A steep gully in alpine terrain. In winter, a couloir is usually filled with snow bound by rocks on either side.

A steep gully or chute. Couloirs form as drainage paths and often channel various types of debris including water, rock, ice, avalanches, etc.

gully, sometimes a potential route. A chute or bowling alley is steep enough for rock or ice fall to be a concern.

An open, steep gully, usually containing ice or snow.

A deep mountain gorge or gully

A steep, relatively narrow groove in a rock wall. Typically, couloirs are wider than "cracks" and smaller than "gullies," and are important as routes up the mountainside.

A couloir (from the French word meaning "corridor,") is a formation of snow or ice, often only defined in winter, forming a breach in a cliff-face. Though often hemmed-in by sheer cliff walls, they may also be formed by the course of a stream or by trees. There is a marked differentiation that should be noted between a couloir and a 'col,' which is the natural, often gradual, depression valley formed by the juncture of two mountain masses.