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English definition of “rat on sb/sth”

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rat on sb/sth

verb uk phrasal verb with rat   /ræt/ slang disapproving us  
to not be loyal to someone, especially by giving away secret information about them, or to fail to do something that you said you would do: He ratted on us. They ratted on the deal.
Translations of “rat on sb/sth”
in Chinese (Traditional) 背叛, (尤指)告密出賣,對…背信棄義…
in Chinese (Simplified) 背叛, (尤指)告密出卖,对…背信弃义…
(Definition of rat on sb/sth from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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