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poison

n. · v.
US //ˈpɔɪzən// UK //pˈɔɪzən// poi·son
  1. 1 toxic substance (n.)
    B1 Intermediate

    a substance that causes illness or death if it enters the body.

    a substance that, through its chemical action, usually kills, injures, or impairs an organism.

    Example

    The label on the bottle had a skull to show it contained poison.

    Example

    The forensic report confirmed that the victim had ingested a lethal dose of a rare organic poison shortly before collapsing.
  2. 2 harmful influence (n.)
    B2 Upper Intermediate

    something that has a very bad or harmful effect on a person or situation.

    an object, influence, or idea that is destructive or corrupting to the mind or a social environment.

    Example

    Jealousy can be a poison that destroys even the strongest friendships.

    Example

    The spread of misinformation acted as a poison within the community, eroding trust in local institutions and creating deep social divisions.
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  1. 3 alcoholic drink (n.)
    C1 Advanced Informal Humorous

    a humorous way to refer to an alcoholic drink.

    a slang reference to an alcoholic beverage, typically used when offering a choice of drinks.

    Example

    Step up to the bar and name your poison.

    Example

    After a long week at the office, he turned to his colleague and asked, 'What's your poison tonight?'

    Teacher's tip

    This is almost exclusively used in the fixed phrases 'name your poison' or 'what's your poison' in social settings.
  2. 4 to kill with toxins (v.)
    B1 Intermediate

    to kill or harm a person or animal using a toxic substance.

    to administer poison to a person or animal; to kill or injure by means of a toxin.

    Example

    The king was afraid that his enemies would try to poison his food.

    Example

    The assassin attempted to poison the diplomat by coating the handle of the car door with a fast-acting nerve agent.
  3. 5 to ruin or corrupt (v.)
    B2 Upper Intermediate

    to make a situation or someone's mind bad or hateful.

    to corrupt or pervert the character or quality of something; to embitter a person's mind.

    Example

    Don't let his lies poison your opinion of the rest of the team.

    Example

    The constant stream of negative propaganda served to poison the minds of the youth against their neighbours.
  4. 6 to pollute (v.)
    B2 Upper Intermediate Science

    to make a place, like a river or the air, dirty and dangerous.

    to contaminate an environment with harmful substances.

    Example

    Chemicals from the old factory continued to poison the local river for years.

    Example

    Industrial runoff began to poison the groundwater, leading to a significant decline in the health of the local ecosystem.
  5. 7 to corrupt data (v.)
    C1 Advanced Technical Computing

    to put false information into a computer system to break it.

    to introduce malicious or false data into a cache or database to subvert a system's operations.

    Example

    The hackers tried to poison the server's cache to redirect users to a fake website.

    Example

    DNS cache poisoning remains a significant threat, as it allows attackers to intercept traffic by providing false IP addresses to legitimate requests.
Origin

From Middle English poysoun, poyson, pusoun, from Old French poison, poisun, from Latin pōtiōnem (“drink, a draught, a poisonous draught, a potion”), from pōtō (“I drink”). See also potion and potable (from the same root). Mostly displaced native Old English ātor. See more at atter.

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