also rathole, 1812 in figurative sense of "nasty, messy place;" rat (n.) + hole (n.). As "bottomless hole" (especially one where money goes) from 1961.
权威例句
1. If I don't send a picture, he will smell a rat.
如果我不寄出照片,他将有所察觉。
2. They were accused of encouraging children to rat on their parents.
他们被指控唆使儿童告发自己的父母。
3. The brown rat has prominent ears and a long scaly tail.
那只棕鼠两只耳朵向前支着,一条长尾巴布满鳞片。
4. Captain Hardnose certainly ran that rat over the hill.
哈得诺思上尉当然要求那个告密者离职了.
5. The lab assistant injected the rat with the new drug.