The most common and most likely answer to this crossword clue is the 8 letter word SLIMMEST
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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 SLIMMEST mean?
SLIMMEST adjective- Slender, thin.
- (of something abstract like a chance or margin) Very small, tiny.
- (rural) Bad, of questionable quality; not strongly built, flimsy.
- Sly, crafty.