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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:

Looking back, Ashby realizes he allowed the enormity of the situation to poison his mind.

From The Wall Street Journal ● Oct. 24, 2026

“At one point in time, Gascón clearly was box office poison and he may still be,” said Roy Behr, a Democratic consultant who isn’t involved in either race.

From Los Angeles Times ● Oct. 22, 2026

A British woman, one of the survivors of Canadian poison seller Kenneth Law, faced him in court on Wednesday to describe how he had exploited her vulnerability.

From BBC ● Sep. 23, 2026

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

“What is the poison tide?” said the robot.

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

Nicola, a poisons information specialist, had received her paddleboard for her 40th birthday just weeks earlier and had been excited about going on the trip run by Lloyd's company, Salty Dog Co Ltd.

From BBC ● Jun. 8, 2026

The soil is packed with poisons, and massive dust storms obscure the sun for months.

From The Wall Street Journal ● Feb. 19, 2026

But then he enacts the scene in which Iago subtly poisons Othello’s mind into believing that his wife is having an affair with a handsome lieutenant.

From Los Angeles Times ● Jan. 17, 2026

She had smell and touch and taste to help her, but touch and taste could be perilous when grinding poisons, and with some of the waif’s more toxic concoctions even smell was less than safe.

From "A Dance with Dragons" by George R. R. Martin

House of Representatives lays out a long-awaited proposal on how to reckon with California’s poisoned marine environment.

From Los Angeles Times ● Oct. 1, 2026

Forensic pathologist Dr Louise Mulcahy said due to the limited remains, it was impossible to test if the child had any natural diseases or if he had been poisoned.

From BBC ● Sep. 17, 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

The Webb score is subtle and insinuating, but it could also be explosive, as in the devastating discovery cue dramatizing the heroine’s realization that she is being poisoned.

From The Wall Street Journal ● Sep. 4, 2026

A poisoned silence floated through the rooms like a big fishnet that Violet alone slashed through with loud recriminations.

From "Jazz" by Toni Morrison

He survived after spending weeks in hospital and has ongoing health issues due to the poisoning.

From BBC ● Oct. 30, 2026

He said a woman and three children were hospitalised "with symptoms of carbon monoxide poisoning" in the region after drone debris fell on a house, causing a fire.

From Barron's ● Oct. 18, 2026

Lead poisoning is "particularly harmful to young children" and can "severely damage the brain and central nervous system", according to the World Health Organization.

From BBC ● Oct. 17, 2026

Under California law, a judge is required to dismiss the poisoning charge if every condition of probation has been followed.

From Los Angeles Times ● Oct. 13, 2026

Dr. Poitevint also described an interesting case of a two- month-old calf that showed symptoms of poisoning by heptachlor.

From "Silent Spring" by Rachel Carson

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