harmful

adjective
harm·​ful | \ ˈhärm-fəl \

Definition of harmful

: of a kind likely to be damaging : injurious

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Other Words from harmful

harmfully \ ˈhärm-​fə-​lē \ adverb
harmfulness noun

Examples of harmful in a Sentence

DDT has been proven to be extremely harmful to the environment.

Recent Examples on the Web

When used over the long-term, laxatives can actually be extremely harmful. Korin Miller, SELF, "5 Things You Need To Know About Using Laxatives For Weight Loss," 2 Jan. 2019 Claim 3: The fragrances in scented candles are seriously harmful to human health. Sam Gutierrez, House Beautiful, "Are Your Favorite Candles Slowly Poisoning You?," 26 Dec. 2018 The problem is when drug use turns compulsive and harmful — creating health risks, leading someone to neglect family and children, driving someone to commit crimes, and so on. German Lopez, Vox, "The simple idea that could help end America’s opioid epidemic," 26 Dec. 2018 Protect against vision loss: Just one cup of kale has more than your whole day's worth of the carotenoids lutein, zeaxanthin, and beta-carotene, which help shield ocular tissues from harmful UV damage and may reduce your risk of cataracts. Jaclyn London, Ms, Rd, Cdn, Good Housekeeping, "Kale Is Actually One of the Healthiest Things You Can Eat," 17 Dec. 2018 Well, okay, but America does commit some harmful acts, even under the best Presidents. Jennifer Wright, Harper's BAZAAR, "Why Men Need to Say Sorry More," 31 July 2018 Thoroughly wash a container that was full of cereal with warm, soapy water before using it again, to remove harmful germs that could contaminate other food. Sarah Brookbank, Cincinnati.com, "Honey Smacks recall: 100 salmonella infections in 33 states," 13 July 2018 Thoroughly wash the container with warm, soapy water before using it again, to remove harmful germs that could contaminate other food. Shelia Poole, ajc, "Kellogg’s recalls “Honey Smacks” over salmonella concerns," 13 July 2018 Pharmacists manage complicated medication regimens requested by multiple prescribers in order to avoid harmful drug interactions. Melissa Stein, STAT, "Privacy laws are hurting the care of patients with addiction," 13 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'harmful.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of harmful

14th century, in the meaning defined above

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Dictionary Entries near harmful

harm's way

harman

harmattan

harmful

harmless

Harmolita

harmonia

Statistics for harmful

Last Updated

7 Jan 2019

Look-up Popularity

Time Traveler for harmful

The first known use of harmful was in the 14th century

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More Definitions for harmful

harmful

adjective

English Language Learners Definition of harmful

: causing or capable of causing damage or harm

harmful

adjective
harm·​ful | \ ˈhärm-fəl \

Kids Definition of harmful

: causing or capable of causing harm : injurious Keep harmful substances away from children.

Other Words from harmful

harmfully \ -​fə-​lē \ adverb

harmful

adjective
harm·​ful

Legal Definition of harmful

: of a kind likely to cause harm

Other Words from harmful

harmfully adverb
harmfulness noun

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More from Merriam-Webster on harmful

Thesaurus: All synonyms and antonyms for harmful

Spanish Central: Translation of harmful

Nglish: Translation of harmful for Spanish Speakers

Britannica English: Translation of harmful for Arabic Speakers

Comments on harmful

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