极度兴奋；疯了，非常生气；颓废；吓坏了，惊慌失措；行为失控，行为异常

1. (verb, slang) To suddenly express anger or excitement in a very visible way.
突然以非常明显的方式表达愤怒或兴奋。

例句：

We freaked out when we won the lottery. 中了奖券,我们兴奋极了。

Mom will freak out when she finds out we broke her vase! 当妈妈发现我们打碎了她的花瓶时，她会大发雷霆的！

I totally freaked out when I heard we’d won tickets to the concert. 当我听说我们赢得了音乐会的门票时，我完全高兴坏了。

2. (verb, slang) To startle or frighten someone. In this usage, a noun or pronoun can be used between “freak” and “out.”
使某人受惊或害怕。在这种用法中，在“freak”和“out”之间可以使用名词或者代词。

例句：

The sight of that huge needle completely freaked me out. 看到那根巨大的针，我完全吓坏了。

He totally freaked out when he saw the armed robbery. 他看到武装抢劫时完全吓坏了。

3. (verb, slang) To experience jarring and frightening side effects (such as hallucinations) due to drug use. In this usage, a noun or pronoun can be used between “freak” and “out.”
由于吸毒而产生的令人不安和可怕的副作用（如幻觉）。在这种用法中，在“freak”和“out”之间可以使用名词或者代词。

例句：

I swore off drugs because my last trip freaked me out so bad.
我发誓不吸毒，因为我上次吸毒产生的迷幻之旅让我太难受了。（吸食毒品后的”心路历程体验”叫做 trip 。因吸毒而引起的不适之感称为 a bad trip，品尝过毒品的人则叫做 tripster 。A trip is a period of intoxication from a hallucinogenic drug such as lysergic acid (LSD) or magic mushrooms (psilocybin). An unpleasant experience of hallucinogen intoxication is known as a “bad trip.”）

4. (noun, slang) A bad experience while taking some mind-altering drug. In this usage, the phrase is often hyphenated or written as one word.
服用某种改变心智（致幻）的毒品时的糟糕经历。在这种用法中，短语通常用连字符或写成一个单词。

I swore off drugs after my last freak-out. 在我上次发疯后，我发誓不再吸毒。

5. (noun, slang) A wild party. In this usage, the phrase is often hyphenated or written as one word.
狂野派对。在这种用法中，短语通常用连字符或写成一个单词。

Someone in our class always throws a real freak-out at the end of the school year. 我们班上总有人在学年结束时举行狂野派对。

freak someone out

to shock or disorient someone. 使某人震惊或迷失方向。

The whole business freaked me out.

I didn’t mean to freak out everybody with the bad news.

freak out (over someone or something) / freak out (at someone or something）

to become very angry or lose control of one’s mind because of someone or something that has happened. 因为某人或某事而变得非常愤怒或失去理智。

I absolutely freaked out over the whole business!

Don’t freak out at me!

freak out (on something)

to lose control of one’s mind because of something, usually a drug. 因为某物，通常是毒品而失去对自己的大脑/思维/意识/精神的控制（失去理智、疯疯癫癫、精神不正常的意思吧）。

She freaked out on the stuff she was smoking.

She took some funny little pills and freaked out immediately.