The most common and most likely answer to this crossword clue is the 10 letter word VENTILATOR
I've seen this crossword clue in The Daily Telegraph
V
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More clues leading to the result VENTILATOR
Buddy explains!
The straight part
We know that "Fan of sickness benefit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fan of sickness benefit = ventilator.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 VENTILATOR mean?
VENTILATOR noun- A device that circulates fresh air and expels stale or noxious air.
- A machine that moves breathable air into and out of the lungs of a patient who is unable to breathe sufficiently.
- A play or an actor so bad as to empty the theater.