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English definition of “rat”

rat

noun [C] uk   /ræt/ us  

rat noun [C] (ANIMAL)

A2 a small rodent, larger than a mouse, that has a long tail and is considered to be harmful: Rats carry disease. I think we've got rats (= there are rats in our house).Rodents and similar animals

rat noun [C] (PERSON)

informal an unpleasant person who deceives others or is not loyalPeople who reveal secrets and tell talesUnpleasant people in generalUnpleasant men
(Definition of rat from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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