The most common and most likely answer to this crossword clue is the 8 letter word INSANITY
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More clues leading to the result INSANITY
- Being out to lunch isn’t any stranger after one
- Elected authority inspires egg mania
- Senselessness involving stupidity, to start with!
- Elected fool into authority? That’s madness
- Madness caused by, ultimately, years in emptiness
- Elected idiot state’s accommodated — there’s no sense in it
- Foolishness claiming Sun may provide lack of balance
- Key conceit does not begin to describe folly
- Unhealthy, dismissing origins of all raging madness
- The point in folly that becomes madness
Buddy explains!

The straight part
We know that "folly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case folly = insanity.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 INSANITY mean?
INSANITY noun- The state of being insane; madness.