Definition of poisonous
- poisonous gas
- poisonous mushrooms
- a poisonous spider
Chocolate is poisonous to dogs.
This species of spider is extremely poisonous.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'poisonous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: causing sickness or death by entering or touching the body : containing poison
: capable of putting poison into another animal's body by biting it
: very harmful or unpleasant
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