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Synonyms

poison

American  
[poi-zuhn] / ˈpɔɪ zən /

noun

  • poisons
    plural
  1. a substance with an inherent property that tends to destroy life or impair health.

  2. something harmful or pernicious, as to happiness or well-being.

    the poison of slander.

  3. Slang. any variety of alcoholic liquor.

    Name your poison!


verb (used with object)

  • poisons,
    present (3rd person singular)
  • poisoned,
    past participle,  past
  • poisoning
    present participle
  1. to administer poison to (a person or animal).

  2. to kill or injure with or as if with poison.

  3. to put poison into or upon; saturate with poison.

    to poison food.

  4. to ruin, vitiate, or corrupt.

    Hatred had poisoned his mind.

    Synonyms:
    taint, pollute, contaminate
  5. Chemistry. to destroy or diminish the activity of (a catalyst or enzyme).

adjective

  1. causing poisoning; poisonous.

    a poison shrub.

poison British  
/ ˈpɔɪzən /

noun

  1. any substance that can impair function, cause structural damage, or otherwise injure the body

  2. something that destroys, corrupts, etc

    the poison of fascism

  3. a substance that retards a chemical reaction or destroys or inhibits the activity of a catalyst

  4. a substance that absorbs neutrons in a nuclear reactor and thus slows down the reaction. It may be added deliberately or formed during fission

  5. informal what would you like to drink?

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to give poison to (a person or animal) esp with intent to kill

  2. to add poison to

  3. to taint or infect with or as if with poison

  4. (foll by against) to turn (a person's mind) against

    he poisoned her mind against me

  5. to retard or stop (a chemical or nuclear reaction) by the action of a poison

  6. to inhibit or destroy (the activity of a catalyst) by the action of a poison

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
poison Idioms  

    More idioms and phrases containing poison


Usage

What does poison mean? A poison is a substance that causes bodily harm or destroys health, The vile was filled with a deadly poison. In this sense, poison can be used as a verb to mean to give poison to a living thing, as in The farmer poisoned his rival’s sheep. Poison can also mean to harm or kill a living thing with poison, as in The king died because he had been poisoned by one of his own knights. And poison can mean to add poison to something, as in The knight poisoned the king’s wine to achieve his wicked goal. More generally, poison can be used to refer to any harmful or corruptive thing, as in Trevor was doomed by the poison of gambling. In this sense, you can use poison as a verb as well, as in Isabelle’s mind was poisoned by the lies contained in the forbidden books. Finally, poison can be used as an adjective to mean something that can cause poisoning, as in There are many poison plants in the woods. Something that contains poison is said to be poisonous, as in He went to the hospital after being bitten by a poisonous spider. Example: Because we handle chemicals that are dangerous poisons in our lab, we take many safety precautions.

Synonym Usage

Poison, toxin, venom are terms for any substance that injures the health or destroys life when absorbed into the system, especially of a higher animal. Poison is the general word: a poison for insects. A toxin is a poison produced by an organism; it is especially used in medicine in reference to disease-causing bacterial secretions: A toxin produces diphtheria. Venom is especially used of the poisons secreted by certain animals, usually injected by bite or sting: the venom of a snake.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of poison

First recorded in 1200–50; Middle English puisun, from Old French, from Latin pōtiōn- (stem of pōtiō ) “drink, potion, poisonous draught.” See potion.

Explanation

Poison is a substance that can harm or even kill you. Arsenic and cyanide are both types of poison—so stay away from them! Mean people can also be poison, so stay away from them too. Poison refers to the harmful substance itself, or the act of giving it to someone. Poison often shows up in murder mysteries because it’s a sneaky way to get rid of someone. We also use poison metaphorically for things that tend to ruin something. A really obnoxious friend who always insists that he knows more than everyone else might poison the atmosphere at a dinner party. Jealousy can poison a good relationship.

Keep Reading on Vocabulary.com

Vocabulary lists containing poison

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Analysts led by Matthew Lofting gently characterized BP’s recent tumultuous history as “chequered” but said the company’s balance sheet improvement means the stock is “no longer a poison pill.”

From MarketWatch ● Sep. 23, 2026

Rather than acting like a conventional fast-acting poison, it disrupts the insect's ability to manufacture enough chitin for the next exoskeleton.

From Science Daily ● Sep. 19, 2026

Police had fingerprint evidence linking a high-profile councillor to a poison pen letter up to 12 months before he went on to target another politician in a "persistent and wicked" hate mail campaign.

From BBC ● Sep. 14, 2026

But as is so often the case in world affairs, there are no good guys in the story and you have to pick your poison.

From Salon ● Aug. 2, 2026

Animals began hurrying to the northern slopes to see the poison tide for themselves.

From "The Wild Robot Protects" by Peter Brown

Wildlife officials had found that many of these poisons worked their way through the food chain, sickening and killing owls, raptors, coyotes and mountain lions.

From Los Angeles Times ● Aug. 16, 2026

If one does not appreciate the nature and importance of the squabble, Freidenberg maintained, one cannot really grasp how totalitarianism poisons every moment.

From The Wall Street Journal ● Apr. 24, 2026

We need to understand why wishing ill on the other side is wrong and why such talk poisons civic life and dooms everyone.

From Los Angeles Times ● Sep. 16, 2025

Andrea was a dental hygienist and a mother-of-one, Nicola - a poisons information specialist and toxicologist - had two children and Morgan was an assistant supermarket manager and trainee firefighter.

From BBC ● Apr. 25, 2025

The collar was set with an enchanted amethyst that Xaro swore would ward her against all poisons.

From "A Clash of Kings" by George R.R. Martin

The attacks escalated this summer, with 16 trees — 13 Jeffrey pines and three white firs — poisoned on three occasions between May and early August.

From Los Angeles Times ● Sep. 19, 2026

Today it is a symbol of a people who still seem poisoned and embittered by an attack that happened a quarter of a century ago.

From Salon ● Sep. 11, 2026

Michael Sheen says an offer to meet Wales' first minister over claims people have been poisoned by decades of exposure to toxic waste dumps "was not taken up".

From BBC ● Sep. 10, 2026

“Art made to get a result is drawing water from a poisoned well.”

From The Wall Street Journal ● Sep. 9, 2026

I climb under the blankets, sure this is what it must feel like to be poisoned.

From "Catching Fire" by Suzanne Collins

Abatement work has exploded in recent years as a more humane alternative to poisoning or killing the birds, Coulson said.

From The Wall Street Journal ● Sep. 27, 2026

But I've had enough of second-guessing myself and panicking I'm poisoning my child if I feed him chicken nuggets, so I've given my shopping list to a dietitian to analyse.

From BBC ● Sep. 26, 2026

In recent weeks, dozens of sea lions suffering from domoic acid poisoning have turned up on beaches from Monterey County to Sonoma County.

From Los Angeles Times ● Sep. 8, 2026

“Obviously, I don’t want a bajillion data centers poisoning the earth,” she says.

From Los Angeles Times ● Aug. 19, 2026

Two days were due to a bout of food poisoning from a taco truck next to Dave’s Marine in Webster, South Dakota.

From "A Heart in a Body in the World" by Deb Caletti

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