The most common and most likely answer to this crossword clue is the 7 letter word SCRUFFY
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The straight part
We know that "Unkempt" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unkempt = scruffy.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 SCRUFFY mean?
SCRUFFY noun- An artificial intelligence researcher who believes that intelligence is too complicated (or computationally intractable) to be solved with the sorts of homogeneous system favoured by the "neats".
- Untidy in appearance.
- Scurfy.