The most common and most likely answer to this crossword clue is the 8 letter word COLLAPSE
I've seen this crossword clue in The Guardian
C
O
L
L
A
P
S
E
More clues leading to the result COLLAPSE
- Entering wood, everyone's about to fall down
- Everyone taking a turn through small wood in fall
- Close up part of church on Hebridean island
- Cave in wooded area swallowing everything up
- Army officer to slip and go to ground
- Everyone turned up when cutting wood in fall
- Cave in woody area: everyone enters the wrong way
- Fail to nab limited parking space on vacation
- Pass by failing to fail
- Fall of everybody climbing trees outside
Buddy explains!

The straight part
We know that "Fall" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fall = collapse.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 COLLAPSE mean?
COLLAPSE noun- The act of collapsing.
- Constant function, one-valued function (in automata theory) (in particular application causing a reset).
- To break apart and fall down suddenly; to cave in.
- To cease to function due to a sudden breakdown; to fail suddenly and completely.
- To fold compactly.
- To hide additional directory (folder) levels below the selected directory (folder) levels. When a folder contains no additional folders, a minus sign (-) appears next to the folder.
- For several batsmen to get out in quick succession
- To cause something to collapse.
- To pass out and fall to the floor or ground, as from exhaustion or other illness; to faint.