- 1causing death or illness if swallowed or absorbed into the body synonym toxic poisonous chemicals/plants This gas is highly poisonous. The leaves of certain trees are poisonous to cattle.
- 2(of animals and insects) producing a poison that can cause death or illness if the animal or insect bites you synonym venomous poisonous snakes a tiny spider with a poisonous bite
- 3extremely unpleasant or unfriendly a poisonous person the poisonous atmosphere in the office
Check pronunciation: poisonous