The most common and most likely answer to this crossword clue is the 8 letter word SENILITY
I've seen this crossword clue in Independent
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More clues leading to the result SENILITY
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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 SENILITY mean?
SENILITY noun- Senescence; the bodily and mental deterioration associated with old age.
- The losing of memory and reason due to senescence.
- An elderly, senile person.