The most common and most likely answer to this crossword clue is the 5 letter word FOVEA
F
O
V
E
A
Buddy explains!
The straight part
We know that "depression" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case depression = fovea.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 FOVEA mean?
FOVEA noun- A slight depression or pit in a bone or organ.
- The retinal fovea, or fovea centralis, responsible for sharp central vision.