noun
drunken frenzy; drunken violence
Refers to the state of becoming violent or uncontrollable when drunk, or the act itself.
彼は酒乱で、酔うと手がつけられなくなる。
He is a violent drunk; once he's drunk, he becomes uncontrollable.
酒乱による事件が増えている。
Incidents caused by drunken violence are increasing.
noun
person prone to drunken violence
Used to describe a person who tends to become violent when drinking.
あの人は酒乱だから、一緒に飲むのは危ない。
That person is a violent drunk, so it's dangerous to drink with them.