The most common and most likely answer to this crossword clue is the 8 letter word UNEASIER
I've seen this crossword clue in The Guardian
U
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E
A
S
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Buddy explains!
The straight part
We know that "More worried" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case more worried = uneasier.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 UNEASIER mean?
UNEASIER adjective- Not easy; difficult.
- Restless; disturbed by pain, anxiety
- Not easy in manner; constrained
- Causing discomfort or constraint