"mad money" in Chinese (Simplified)
应急钱备用金
Definition
为应急、意外情况或必须时留出的备用钱（比如约会不顺时回家的路费）。有时也指为花在有趣或冲动事情上的额外储蓄。
Usage Notes (Chinese (Simplified))
属口语表达，多用于美国英语。最早指女性约会时以备回家的钱，现在泛指应急备用金或零用钱。常和“存点mad money”搭配使用。
Examples
She always keeps some mad money in her wallet in case she needs a taxi home.
她的钱包里总有一些**应急钱**，以防需要打车回家。
I set aside some mad money every month for emergencies.
我每个月都会留一点**应急钱**以防万一。
He used his mad money to buy a surprise gift for his friend.
他用**备份钱**给朋友买了一个惊喜礼物。
Keep some mad money on you—you never know when you might need it.
随身带点**应急钱**吧——你永远不知道什么时候会用到。
After paying my bills, there's a bit of mad money left for coffee or a movie.
付完账单后还有点**零花钱**，可以喝咖啡或看电影。
When I was a kid, my grandma always told me to hide some mad money in my shoe.
小时候，奶奶总是让我把一些**应急钱**藏在鞋子里。