avalanche

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A fall or slide of a large mass, as of snow or rock, down a mountainside.
2. n. A massive or overwhelming amount; a flood: received an avalanche of mail.
3. v. To fall or slide in a massive or overwhelming amount.
4. v. To overwhelm; inundate.

Century Dictionary and Cyclopedia

1. n. The fall or sliding down of a mass of snow or ice from a mountain-slope. The sliding down of ordinary snow is, in high snow-covered mountains, an event of frequent occurrence, and is generally not dangerous or destructive, since it mostly takes place high above habitations and forests. Partly consolidated snow, or névé however, is sometimes set in motion in large quantities, and such an occurrence may be productive of very serious injury, especially to the forests below. Small glaciers sometimes detach themselves from their rocky beds and fall into the valley below; such events are rare, but have sometimes been attended by very disastrous results. The more terrible catastrophes which have occurred, and by which, especially in the Alps, whole villages have been buried, have been due to the sliding down of a portion of the rock itself of which the mountain was formed. These “rock-avalanches,” as they are sometimes called, are more properly denominated land-slips or land-slides. See landslip, land-slide.
2. n. Hence—2. Anything resembling an avalanche in suddenness and destructiveness: as, an avalanche of misfortunes.

Wiktionary

1. n. A large mass or body of snow and ice sliding swiftly down a mountain side, or falling down a precipice.
2. n. A fall of earth, rocks, etc., similar to that of an avalanche of snow or ice.
3. n. A sudden, great, or irresistible descent or influx of anything.
4. n. Anything like an avalanche in suddenness and overwhelming quantity (like a barrage, blitz, etc).
5. v. intransitive To descend like an avalanche.
6. v. transitive To come down upon; to overwhelm.

GNU Webster's 1913

1. n. A large mass or body of snow and ice sliding swiftly down a mountain side, or falling down a precipice.
2. n. A fall of earth, rocks, etc., similar to that of an avalanche of snow or ice.
3. n. A sudden, great, or irresistible descent or influx of anything.

WordNet 3.0

1. n. a slide of large masses of snow and ice and mud down a mountain
2. v. gather into a huge mass and roll down a mountain, of snow
3. n. a sudden appearance of an overwhelming number of things