The most common and most likely answer to this crossword clue is the 9 letter word AVALANCHE
I've seen this crossword clue in The Times
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More clues leading to the result AVALANCHE
- A snowdrop?
- A new church in a valley that may be seen coming down mountain
- Big fall of lava recalled beside a new Church
- Guerrilla supporting a wild naval barrage
- Snowslip burying a northern church in a dale
- . Landslide victory gained by one in a Chanel ensemble
- Fall for an item of linen hotel included
- It slides down over husband inside a bed cover
- Barrage of hot rock set up an old rebel
- A piece of drapery hides her top and big slip
Buddy explains!

The straight part
We know that "A snowdrop" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a snowdrop = avalanche.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does AVALANCHE mean?
AVALANCHE noun- A large mass or body of snow and ice sliding swiftly down a mountain side, or falling down a precipice.
- A fall of earth, rocks, etc., similar to that of an avalanche of snow or ice.
- (by extension) A sudden, great, or irresistible descent or influx; anything like an avalanche in suddenness and overwhelming quantity.
- To descend like an avalanche.
- To come down upon; to overwhelm.
- To propel downward like an avalanche.