'coup d'état' has 9 letters but is not one word.
'revolution' has 10 letters but, ia a process...
A flash flood?
A five-letter word for sudden movement is probably "start." Make sure the "d" is correct.
boom
One choice is the word ambush.
crackdown - for the That's Life! puzzlers
The coup was meant to overthrow the government. The overthrow attempt did not work.
Another word for overthrow is defeat. Also the word destroy is another example. You could use the word seize as a synonym of the word overthrow.
revolution
Crash is a 5-letter word that can refer to "a sudden noise".
A coup de 'etat.
Overthrow means a removal from power/ to put an end to. The rebels chose to overthrow the government. Be creative and think up your own sentence.
fervent
onrush
Sudden
Unexpected
craving
jerk, jolt