The most common and most likely answer to this crossword clue is the 7 letter word CAITIFF
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The straight part
We know that "Mean person" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mean person = caitiff.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 CAITIFF mean?
CAITIFF noun- A base or despicable person; a wretch
- A captive or prisoner, particularly a galley slave
- A villain, a coward or wretch
- Especially despicable; cowardly