poisonous

play
adjective poi·son·ous \ˈpȯiz-nəs, ˈpȯi-zən-əs\

Definition of poisonous

  1. 1 :  destructive, harmful

  2. 2a :  having the properties or effects of poison poisonous gasb :  producing a toxic substance that causes injury or death when absorbed or ingested poisonous mushrooms; also :  venomous a poisonous spider

  3. 3 :  spiteful, malicious

poisonously

adverb

Examples of poisonous in a Sentence

  1. Chocolate is poisonous to dogs.

  2. This species of spider is extremely poisonous.

Recent Examples of poisonous from the Web

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.

First Known Use of poisonous

15th century


POISONOUS Defined for English Language Learners

poisonous

play
adjective

Definition of poisonous for English Language Learners

  • : 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


POISONOUS Defined for Kids

poisonous

play
adjective poi·son·ous \ˈpȯi-zən-əs\

Definition of poisonous for Students

  1. :  containing poison :  having or causing an effect of poison poisonous mushrooms


Medical Dictionary

poisonous

play
adjective poi·son·ous \ˈpȯiz-nəs, -ən-əs\

Medical Definition of poisonous

  1. 1:  having the properties or effects of poison poisonous gas

  2. 2:  producing a toxic substance that causes injury or death when absorbed or ingested poisonous frogs and plants; also :  venomous



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