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.
For every person who happily sets 4:00 a.m. alarms on race morning, there’s another convinced the sport is too hard, too boring, or a waste of time, if not outright harmful. Cindy Kuzma, SELF, 25 Apr. 2025 Confusing a congressional edict to end segregation with DEI policies that have no genesis in the Black Civil Rights movement to end Jim Crow is historically ignorant, disrespectful, and harmful to the urgent need to focus on resolving continuing racial inequalities in public education. Raymond Pierce, Forbes.com, 25 Apr. 2025 The Lost Screen Memorial is comprised of 50 smartphones, each displaying the lock screen photo of a child whose life was cut short, stemming from the harmful effects of social media. Elizabeth Rosner, People.com, 24 Apr. 2025 Efforts to slash staff, funding and programs at EPA are leaving families even more vulnerable to harmful air pollution. Ross Rosenfeld, MSNBC Newsweek, 23 Apr. 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

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Cite this Entry

“Harmful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harmful. Accessed 28 Apr. 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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