lose one's lunch是个美式俚语，字面意思是“丢掉了午餐”，实际表达是“呕吐，没胃口”（to throw up/vomit）。你还可以用toss one’s lunch来表达觉得恶心。

例句：

I felt like I was going to lose my lunch from seasickness out on that boat.

我感觉我要因为晕船恶心吐了。

The smell was so disgusting that several people tossed their lunches right then and there.

这味道太恶心了，许多人吐得到处都是。