The most common and most likely answer to this crossword clue is the 8 letter word DEVIATES
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The straight part
We know that "Strays" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case strays = deviates.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 DEVIATES mean?
DEVIATES noun- A person with deviant behaviour; a deviant, degenerate or pervert.
- A value equal to the difference between a measured variable factor and a fixed or algorithmic reference value.
- To go off course from; to change course; to change plans.
- To fall outside of, or part from, some norm; to stray.
- To cause to diverge.