The most common and most likely answer to this crossword clue is the 5 letter word GORGE
I've seen this crossword clue in Financial Times
G
O
R
G
E
More clues leading to the result GORGE
- Stuff oneself with something close to Cheddar?
- Stuff in deep narrow valley
- Stuff big hole
- Stuff essential for giving or getting
- Pig's blood — extra gallon included
- Stuff in small canyon
- Butchery involves good stuff
- Booze thrown up, with European revealing stomach contents
- Defender of England, not Europe? Get stuffed!
- Tipple in the main thrown up, ultimate in crude stuff
Buddy explains!
The straight part
We know that "deep depression" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deep depression = gorge.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.