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English definition of “poisonous”

poisonous

adjective uk   /ˈpɔɪ.zən.əs/ us  
B2 very harmful and able to cause illness or death: poisonous chemicals Can you tell the difference between poisonous mushrooms and edible varieties? B2 A poisonous animal or insect uses poison in order to defend itself: a poisonous snake very unpleasant and unkind: He said some poisonous things to me.
(Definition of poisonous from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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