The most common and most likely answer to this crossword clue is the 10 letter word GRIEVANCES
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The straight part
We know that "complaints" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case complaints = grievances.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 GRIEVANCES mean?
GRIEVANCES noun- Something which causes grief.
- A wrong or hardship suffered, which is the grounds of a complaint.
- Feelings of being wronged; outrage.
- A complaint or annoyance.
- A formal complaint, especially in the context of a unionized workplace.
- Violation of regulations or objectionable behavior.