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1. A slide of large masses of snow and ice and mud down a mountain
   - snowslide [N. Amer]
    
2. A sudden appearance of an overwhelming number of things
   "the program brought an avalanche of mail"

1. Gather into a huge mass and roll down a mountain, of snow

Derived forms: avalanches, avalanching, avalanched

Type of: come down, descend, fall, go down, happening, natural event, occurrence, occurrent, sink, slide

Encyclopedia: Avalanche, Wisconsin