The most common and most likely answer to this crossword clue is the 8 letter word DISQUIET
I've seen this crossword clue in Financial Times
D
I
S
Q
U
I
E
T
Buddy explains!

The straight part
We know that "Worry" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case worry = disquiet.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 DISQUIET mean?
DISQUIET noun- Lack of quiet; absence of tranquility in body or mind
- To make (someone or something) worried or anxious.
- Deprived of quiet; impatient, restless, uneasy.