insane and believed to be affected by the phases of the moon
例句
用作名词(n.)
People in this town know him as a lunatic.这个镇上的人们称他为疯子。
You're driving on the wrong side of the road, you lunatic!你现在是逆行开车，你这个蠢材！
I really don't know what kind of man he really is; on one occasion, he is normal, and on another, he acts like a lunatic.我真不了解他到底是怎样的人; 一会儿正常，一会儿又像个疯子。
用作形容词(adj.)
The man's lunatic behavior is a menace to society.那个人的疯狂行为构成对社会的威胁。
