Meaning & Definition
adjective
capable of causing illness or death, especially by absorbing or consuming poison.
The plant's bright berries are highly poisonous and should not be eaten.
containing or being a poison; toxic.
Certain mushrooms are known to be poisonous, and it's important to identify them correctly.
harmful or detrimental to health.
The spill from the factory released poisonous chemicals into the river.
malicious or full of spite.
His poisonous attitude made it difficult for anyone to work with him.
Etymology
Middle English, from Old French 'poison', from Latin 'potionem' meaning a drink or potion.
Common Phrases and Expressions
poisonous gas:
A gas that is toxic to humans or animals.
poisonous relationship:
A relationship that is emotionally harmful and toxic.
poisonous plant:
A plant that contains harmful substances.
Slang Meanings
Extremely negative or harmful behavior.
Her gossiping is really poisonous, it just spreads negativity.
Someone or something that brings harm to a group or situation.
He's a poisonous influence on the team; we need to make a change.