The most common and most likely answer to this crossword clue is the 4 plus 4 letter word COME DOWN
C
O
M
E
D
O
W
N
Buddy explains!

The straight part
We know that "degenerate" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case degenerate = come down.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 COME DOWN mean?
COME DOWN noun- A sudden drop to a lower status, condition or level; a disappointment or letdown
- A calm, mellow period experienced after the initial high from taking drugs