[adjective]Something poisonous is very harmful and can cause illness or death.Dangerously high levels of poisonous chemicals were found in the river.Can you tell the the difference between poisonous mushrooms and edible varieties?(figurative) He said some poisonous (= very unpleasant) things to me.
POISONOUS
Meaning of POISONOUS in English
Cambridge English vocab. Кембриджский английский словарь. 2012