The most common and most likely answer to this crossword clue is the 10 letter word PREVALENCE
I've seen this crossword clue in The Daily Telegraph
P
R
E
V
A
L
E
N
C
E
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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 PREVALENCE mean?
PREVALENCE noun- The quality or condition of being prevalent; wide extension or spread.
- The total number of cases of a disease in a given statistical population at a given time, divided by the number of individuals in that population.