The most common and most likely answer to this crossword clue is the 8 letter word DOWNTURN
I've seen this crossword clue in The Daily Telegraph
D
O
W
N
T
U
R
N
More clues leading to the result DOWNTURN
- Sad act in decline
- Drop of tea, we hear, in blue vessel
- Change after drink causes decline
- Decline drink before performance
- Decline drink and go
- Decline drink before round
- Go to the east of county in economic decline
- Drop drawers in beginning private act
- Deterioration of performer in part of NI?
- Maybe Bangor’s act is in decline
Buddy explains!

The straight part
We know that "Deterioration" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deterioration = downturn.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 DOWNTURN mean?
DOWNTURN noun- A downward trend, or the beginnings of one; a decline.
- To turn downwards
- To decline