The most common and most likely answer to this crossword clue is the 6 letter word UNREST
I've seen this crossword clue in The Guardian
U
N
R
E
S
T
More clues leading to the result UNREST
- Residence for one in group causing disturbance
- Disturbance in Cajun restaurant
- Commotion near centre of Preston, close to university
- Rebellion when peacekeepers take break?
- Disquiet caused by right tunes in wrong order
- Rebellion contained by gun restrictions
- Tuner’s dealt with discord
- University exceptionally stern as the result of disturbance
- Dissent remains after new uniform rejected
- A French king is, in his country, bringing dissatisfaction
Buddy explains!

The straight part
We know that "Rebellion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rebellion = unrest.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 UNREST mean?
UNREST noun- A state of trouble, confusion and turbulence, especially in a political context; a time of riots, demonstrations and protests.