poisonous

[poi-zuh-nuhs] / ˈpɔɪ zə nəs /

ADJECTIVE

harmful

Synonyms

STRONGEST

dangerous deadly destructive fatal lethal noxious pernicious toxic venomous vicious virulent

WEAK

bad baleful baneful corrupt corruptive deleterious detrimental evil hurtful infective malicious malignant mephitic miasmatic morbid mortal nocuous noisome peccant pestiferous pestilential poison septic toxicant toxiferous viperous

Antonyms

STRONGEST

gentle good harmless healthful healthy helpful kind life-giving nice nonpoisonous wholesome

WEAK

benevolent non-toxic

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.

“Recent rains have contributed to the resurgence of poisonous wild mushrooms in California, including in Napa,” said a statement from Dr. Christine Wu, Napa County’s public health officer.

From Los Angeles Times • May 15, 2026

Unicorn horns can make poisonous water safe to drink, while a griffin’s feather can restore sight.

From The Wall Street Journal • Apr. 16, 2026

It’s got poisonous lead in it from paint.

From Salon • Mar. 6, 2026

But there are dozens of other poisonous snake species for which India does not have targeted antivenom.

From BBC • Feb. 1, 2026

So likewise those living creatures that are enemies to poisonous things, and swallow them up without danger, may shew us that such poisons will cure the bitings and blows of those creatures.

From "The Invention of Science" by David Wootton

Vocabulary lists containing poisonous

Week 4 Vocabulary

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Harmful, List 2

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-ious, -eous, -ous

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