The most common and most likely answer to this crossword clue is the 10 letter word DEGENERATE
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More clues leading to the result DEGENERATE
- Decline of French commander English think highly of?
- Decline of French commander briefly travelling east at the front
- Rascal went back on a promise about boiling tea
- Slowly but surely go down? Pervert!
- Study English judge jailing, say, reprobate
- Agreed, teen perverted and immoral
- Decline of French produce
- Go back on one’s promise? That’s raised during engagement. It’s ignoble!
- Fallen Greek character went back up
- Decline of French taxonomic groups — those without heart
Buddy explains!

The straight part
We know that "Fallen" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fallen = degenerate.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 DEGENERATE mean?
DEGENERATE noun- One who is degenerate, who has fallen from previous stature; an immoral person.
- To lose good or desirable qualities.
- To cause to lose good or desirable qualities.
- (of qualities) Having deteriorated, degraded or fallen from normal, coherent, balanced and desirable to undesirable and typically abnormal.
- (of a human or system) Having lost good or desirable qualities.
- (of an encoding or function) Having multiple domain elements correspond to one element of the range.
- Relating to degeneracy
- Having the same quantum energy level.