Sudden appearance of an overwhelming mass (9)

I believe the answer is:

avalanche

(Other definitions for avalanche that I've seen before include "heavy snowfall" , "Landslide of snow" , "Sudden overwhelming quantity" , "Mass of sliding snow or rock" , "Mountainside fall" .)

I've seen this clue in The Guardian.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.