a small animal with a long tail, that looks like a large mouse, usually considered a pest (= an animal which is disliked because it destroys food or spreads disease) 老鼠；耗子 
rat poison 老鼠药 The police are all over town. He’s caught, like a rat in a trap. 警察遍布全城。他被抓住了，就像是陷阱里的老鼠。
Extra ExamplesTopics Animalsb2Rats had gnawed through the wires. 老鼠把电线啃断了。 The dog was a useful rat catcher in the warehouse. 狗是仓库中有用的捕鼠能手。 a rat-infested cellar 老鼠横行的地下室
Oxford Collocations Dictionaryadjective- black
- brown
- lab
- …
- scurry
- scuttle
- gnaw
- …
- catcher
- droppings
- poison
- …
- (informal, disapproving)
an unpleasant person, especially somebody who treats their partner or friends badly, for example by leaving them or cheating them 讨厌的人；卑鄙的小人；骗子 You mean he just walked out on her after fifteen years? What a rat! 你是说十五年后他就抛弃了她？好一只老鼠！
Word OriginOld English ræt, probably of Romance origin; reinforced in Middle English by Old French rat. The verb dates from the early 19th cent.
Idioms
(like rats) deserting/leaving a sinking ship
- (humorous, disapproving)
used to talk about people who leave an organization, a company, etc. that is having difficulties, without caring about the people who are left （比喻只顾自己而离开处于困境中的机构等）（像）逃离沉船（的老鼠）
smell a rat
- (informal)
to suspect that something is wrong about a situation 怀疑事情不妙；感觉情况不对