adj
poisonous
POY-zuh-nuhs
adj
1
Containing enough poison to harm or kill if touched, eaten, or breathed in.
"Some poisonous berries look almost identical to edible ones."
"The factory leaked poisonous gas into the air."
2
Deeply harmful, especially to a person's attitude or a relationship.
"He left the company because of its poisonous work culture."
How to Use Poisonous
Learner’s notesIn plain EnglishCapable of causing serious harm — either physically toxic, or (figuratively) toxic to a relationship or environment.
Common mistake
In everyday English, "poisonous" and "venomous" are often used interchangeably, though strictly venomous describes animals that inject poison by biting or stinging, while poisonous describes things harmful if touched or eaten.
Easily confused with
Common pairings
poisonous snake
poisonous gas
poisonous atmosphere
Word Forms
more poisonous comparative, most poisonous superlative
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Some _____ berries look almost identical to edible ones.
Etymology
From poison + the adjective suffix -ous.