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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.

Proponents of raw milk say that pasteurization, a heating process that kills harmful bacteria, removes natural health benefits and that warnings around the consumption of raw milk are overstated.

From The Wall Street Journal • Apr. 11, 2026

In addition to California and West Virginia, several states are taking extra measures to limit harmful food additives.

From Salon • Apr. 11, 2026

The models could be employed for harmful ends either “inadvertently or intentionally,” he said.

From MarketWatch • Apr. 11, 2026

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

From Science Daily • Apr. 9, 2026

Many of the chemical agents in this alarming melange imitate and augment the harmful effects of radiation, and within the groups of chemicals themselves there are sinister and little-understood interactions, transformations, and summations of effect.

From "Silent Spring" by Rachel Carson

Vocabulary lists containing harmful

Earth Day

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Unfavorable

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