a slide of large masses of snow and ice and mud down a mountain
"The heavy storm caused an avalanche that swept massive amounts of snow and ice down the steep mountain side, burying the village below."
a sudden appearance of an overwhelming number of things
"the program brought an avalanche of mail"
A large mass or body of snow and ice sliding swiftly down a mountain side, or falling down a precipice.
"A massive avalanche swept down the steep mountain side, burying the cabin in its path."
In plain English: An avalanche is when a huge pile of snow suddenly breaks loose and rushes down a mountain, often carrying rocks and trees with it.
"The heavy snow caused an avalanche that buried several cabins in the mountains."
Usage: Use this word to describe the sudden collapse of a massive amount of snow or rock that tumbles rapidly downhill. It can also function as a verb when something overwhelms another person with excessive force or quantity, such as being buried under paperwork.
To descend like an avalanche.
"The crowd surged forward and descended on the stage like an avalanche."
In plain English: To avalanche means to fall down very quickly and with great force, usually because something big breaks apart under its own weight.
"An avalanche of letters came pouring into my mailbox after I won the lottery."
The word "avalanche" comes from the French avalanche, which is a blend of words meaning "downhill" and referring to snow. Its ultimate roots trace back through Vulgar Latin to the concept of slipping or sliding down a slope.