harmful

adjective

harm·​ful ˈhärm-fəl How to pronounce harmful (audio)
: of a kind likely to be damaging : injurious
harmfully 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Market intervention is always and everywhere harmful simply because markets are people. John Tamny, Forbes, 19 Jan. 2025 In an October 2022 article in the Montreal Gazette, Bryn Austin, a professor at Harvard T.H. Chan School of Public Health, highlighted how BMI can lead to harmful outcomes. David Faris, Newsweek, 19 Jan. 2025 And tests of raw products show that they are frequently contaminated with harmful viruses and bacteria such as salmonella and E. coli. Brenda Goodman, CNN, 18 Jan. 2025 Some women have expressed concern that the ERA could be more harmful than helpful. Jackson Walker, Baltimore Sun, 17 Jan. 2025 See all Example Sentences for harmful 

Word History

First Known Use

14th century, in the meaning defined above

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

Dictionary Entries Near harmful

Cite this Entry

“Harmful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harmful. Accessed 22 Jan. 2025.

Kids Definition

harmful

adjective
harm·​ful ˈhärm-fəl How to pronounce harmful (audio)
: causing damage : injurious
harmfully adverb
harmfulness noun

Legal Definition

harmful

adjective
harm·​ful
: of a kind likely to cause harm
harmfully adverb
harmfulness noun

More from Merriam-Webster on harmful

Last Updated: - Updated example sentences
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