- a mass of loosened snow, earth, rocks, etc. suddenly and swiftly sliding down a mountain, often growing as it descends
- any large, overwhelming quantity that comes suddenly: an avalanche of mail, of blows, etc.
Origin of avalancheFrench (altered after avaler, to descend) from lavanche from Provençal lavanca from an unverified form lavenca, probably a pre-Roman word in a non-IE language of northern Italy
transitive verb-·lanched·, -·lanch·ing