The most common and most likely answer to this crossword clue is the 8 letter word PRIMMEST
I've seen this crossword clue in The Sunday Telegraph
P
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More clues leading to the result PRIMMEST
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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 PRIMMEST mean?
PRIMMEST adjective- Prudish, straight-laced
- Formal; precise; affectedly neat or nice