The most common and most likely answer to this crossword clue is the 10 letter word UNSTRESSED
U
N
S
T
R
E
S
S
E
D
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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 UNSTRESSED mean?
UNSTRESSED adjective- (of a vowel) not stressed or accentuated
- Not subject to stress