An avalanche is a large mass of snow and ice that suddenly breaks loose and slides down a mountainside, while a landslide is a sudden collapse and downhill movement of soil, rock, and debris. Memory hook: avalanche is snow, landslide is land — the material is right there in the word.
The core difference
Avalanche and landslide both describe sudden downhill collapses, but one is made of snow and ice while the other is made of soil, rock, and debris.
- avalanche — a mass of snow and ice sliding down a mountainside: The skiers had to be rescued after an avalanche blocked the only path down.
- landslide — a collapse of soil, rock, and debris moving downhill: Heavy rain triggered a landslide that blocked the mountain road.
How to tell them apart
The two share the same sudden, downhill motion, which is why they get mixed up, but the material involved settles it every time. An avalanche is snow and ice, the hazard skiers and mountaineers train for. A landslide is earth, rock, and debris, often triggered by heavy rain loosening a slope, as when a mountain road is blocked or homes are destroyed.
Both words have also picked up figurative senses worth knowing. An avalanche can describe any sudden, overwhelming rush, such as an avalanche of complaints, while a landslide describes an overwhelming victory in an election or vote.
