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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.

This type of fat is generally not harmful and is actually necessary for overall health.

From Science Daily • May 7, 2026

They also spoke out against "pervasive, opaque and harmful industrial subsidies, market-distortive practices of state-owned enterprises, and all forms of forced technology transfer".

From Barron's • May 6, 2026

Our investigation also uncovered potentially harmful advice from Lisa Clegg, known online to her nearly 100,000 Instagram followers as the "Blissful Baby Expert".

From BBC • May 5, 2026

The memo now tasks those offices with conducting toxicity assessments and brings an end to the program that has powered the EPA’s efforts to protect people from harmful chemicals.

From Salon • May 5, 2026

“If they tell you it is all right, you should pray with your tefillin. But only if they tell you it is all right and will not be harmful to your head or your eye.”

From "The Chosen" by Chaim Potok

Vocabulary lists containing harmful

Earth Day

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Unfavorable

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