The most common and most likely answer to this crossword clue is the 6 letter word FAULTY
I've seen this crossword clue in Independent
F
A
U
L
T
Y
More clues leading to the result FAULTY
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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 FAULTY mean?
FAULTY adjective- Having or displaying faults; not perfect; not adequate or acceptable.
- At fault, to blame; guilty.