Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “poison”

poison

noun  /ˈpɔɪ·zən/ us  

poison noun (SUBSTANCE)

[C/U] a substance that causes illness or death if swallowed, absorbed, or breathed into the body: [U] poison gas [C] Some cleaning products are poisons. [U] He sprayed the weeds with poison.
poisonous
adjective  /ˈpɔɪ·zə·nəs/ us  
The mushrooms they picked were poisonous.

poison

verb [T]  /ˈpɔɪ·zən/ us  

poison verb [T] (CAUSE HARM)

to cause serious harm to something: Jealousy poisoned our relationship. I don’t see why you think TV poisons people’s minds (= influences them in a bad way).

poison verb [T] (SUBSTANCE)

to cause a person or animal to take in poison, or to add poison to food or a liquid: He thinks someone is trying to poison him. Her tea was poisoned.
(Definition of poison from the Cambridge Academic Content Dictionary © Cambridge University Press)
What is the pronunciation of poison?
Add Cambridge dictionaries to your browser to your website

More American English definitions for “poison”

Definitions of “poison” in other dictionaries

Word of the Day

microbrewery

a small company that makes beer, usually using traditional methods, and often has a restaurant where its beer is served

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More