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Showing results for harmful.
Definitions

harmful

[hahrm-fuhl] / ˈhɑrm fəl /
ADJECTIVE
injurious, hurtful
Synonyms
STRONGEST
adverse bad catastrophic damaging destructive detrimental disadvantageous disastrous inimical noxious painful pernicious risky ruinous sinful toxic unhealthy unsafe
WEAK
baleful baneful calamitous cataclysmic consumptive corroding corrupting crippling deleterious dire evil harassing incendiary internecine malefic malicious malignant menacing mischievous murderous nocuous pestiferous pestilential sinister subversive undermining unwholesome virulent
Antonyms
STRONGEST
advantageous aiding assisting beneficial favorable fortunate good harmless healthy helpful honest kind lucky profitable safe upright

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.

By identifying harmful gut sugars as a driver of disease, researchers now have new targets for treatment.

From Science Daily • Apr. 9, 2026

"Many parents are already talking to their children about harmful content or screen time, but privacy often gets overlooked," Justine Roberts, founder of Mumsnet, said.

From BBC • Apr. 6, 2026

“When I see an ICE agent doing something radically bad and harmful, I can recognize that that is a person who is suffering and being oppressed by a deep darkness.”

From Salon • Apr. 6, 2026

“The best thing you can say about them is that they weren’t as harmful people thought they would be,” said Scott Lincicome, the vice president of general economics at the Cato Institute in Washington, D.C.

From Barron's • Apr. 2, 2026

When they are otherwise, the outcome will always be harmful either for one or the other.

From "The Prince" by Niccolò Machiavelli