That man is a homicidal maniac.

那人是个嗜杀成性的疯子。

《柯林斯英汉双解大词典》

If I were going to beget a child knowing that the child was going to be a homicidal maniac, I should be responsible for his crimes.

如果，我知道我即将生出的小孩以后是一个杀人狂，那么我就有责任对他的罪行负责。

youdao

You have the general layman's idea of a homicidal maniac - a man who runs amok with a knife, a man more or less foaming at the mouth.

这完全是外行人对杀人狂的看法，以为他一定会拿着刀到处乱跑，嘴边不时吐些白沫。

youdao

There they find, in ascending order of strangeness, Dr. Cleave (Ian McKellen) and his brooding patient Edgar (Marton Csokas), whose career includes stints first as a sculptor and then as a homicidal maniac.

NEWYORKER: Asylum

When a character becomes a franchise, there is only so much repetition that he or she can take before sliding into parody, and there is something distasteful in the thought that we are being urged to treat a homicidal maniac as a lovable rogue.

NEWYORKER: Red Dragon

You know, like not trying to reanimate a six foot tall homicidal maniac in an abandoned castle, or not looking into the eyes of Count Dracula.

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