crack up

英 [kræk ʌp]

美 [kræk ʌp]

（因精神压力大而）垮掉，崩溃; （使）大笑

柯林斯词典

PHRASAL VERB (因精神压力大而)垮掉，崩溃
If someonecracks up, they are under such a lot of emotional strain that they become mentally ill.
1. She would have cracked up if she hadn't allowed herself some fun.
  她若是没给自己找点乐趣的话，早就崩溃了。
PHRASAL VERB (使)大笑
If youcrack upor if someone or somethingcracksyouup, you laugh a lot.
1. She told stories that cracked me up and I swore to write them down so you could enjoy them too...
  她讲了几个令我捧腹大笑的故事，我一定要写下来，好让你也乐乐。
2. We all just cracked up laughing.
  我们都不禁哈哈大笑起来。

verb