harmful

[hahrm-fuhl]

adjective

1. causing or capable of causing harm; injurious.

   a harmful idea;

   a harmful habit.

   Synonyms: deleterious, damaging, detrimental, hurtful
   Antonyms: beneficial

harmful

/ ˈhɑːmfʊl /

adjective

1. causing or tending to cause harm; injurious

Other Word Forms

• harmfully adverb
• harmfulness noun
• quasi-harmful adjective
• quasi-harmfully adverb
• unharmful adjective
• unharmfully adverb

Word History and Origins

Origin of harmful¹

First recorded before 1000; Middle English; Old English hearmful; harm, -ful

Example Sentences

These conditions are driven by harmful buildups in the brain made of misfolded amyloid proteins.

Read more on Science Daily

Campaigners and the government say the law is necessary to protect children from harmful content and algorithms that can promote it to users.

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As human cells grow older or are harmed by degenerative disorders such as Alzheimer's disease, or by exposure to harmful agents like chemotherapy drugs, their ability to generate energy steadily drops.

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Counterfeit football kits are not a new issue, but some experts have raised concerns that the sub-standard materials used in their manufacture could even be harmful.

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Rodriguez said there are “very valid reasons” to pay attention to alerts but that minimizing their harmful effects is crucial for economic recovery.

Read more on Los Angeles Times

Related Words

• adverse 
• bad 
• catastrophic 
• damaging 
• destructive 
• detrimental 
• disadvantageous 
• disastrous 
• inimical 
• noxious 
• painful 
• pernicious 
• risky 
• ruinous 
• sinful 
• toxic 
• unhealthy 
• unsafe