free-for-all
noun [ S ] uk/ˌfriː.fəˈrɔːl/ us/ˌfriː.fəˈrɑːl/
不受控制的局面，人人均可为所欲为的情形，自由放任
a violent situation or argument that a lot of people join in
The fight on the basketball court turned into a free-for-all. 篮球场上的打斗很快便失控了。
Synonym: brawl