The most common and most likely answer to this crossword clue is the 14 letter word DISEASE-RIDDEN
D
I
S
E
A
S
E
-
R
I
D
D
E
N
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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 DISEASE-RIDDEN mean?
DISEASE-RIDDEN adjective- Dominated by disease.