The most common and most likely answer to this crossword clue is the 9 letter word EMPHYSEMA
I've seen this crossword clue in The Guardian
E
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More clues leading to the result EMPHYSEMA
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The straight part
We know that "Condition" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case condition = emphysema.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 EMPHYSEMA mean?
EMPHYSEMA noun- An abnormal accumulation of air or other gas in tissues, most commonly the lungs.
- Pulmonary emphysema, a chronic lung disease, one type of chronic obstructive pulmonary disease.