harmful

adjective
harm·​ful | \ ˈhärm-fəl How to pronounce harmful (audio) \

Definition of harmful

: of a kind likely to be damaging : injurious

Other Words from harmful

harmfully \ ˈhärm-​fə-​lē How to pronounce harmful (audio) \ 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 With all that in mind, the breast is best message is harmful to new mothers and mothering folks for a number of reasons. Allison Tsai, SELF, 23 June 2022 The recall movement, which now seems to have a chance to collect enough signatures to force Gascón into a recall election, has largely been animated by the idea that the district attorney’s policies are harmful to crime victims. James Queally, Los Angeles Times, 21 June 2022 True people of Indiana and Kentucky, told the school board during public comment that the mascot portrayal is harmful to all students. Mj Slaby, The Indianapolis Star, 16 June 2022 The American Psychological Association says conversation therapy is not based on science and is harmful to a participant’s mental health. Will Weissert, Sun Sentinel, 15 June 2022 The American Psychological Association says conversion therapy is not based on science and is harmful to a participant’s mental health. Will Weissert, Anchorage Daily News, 15 June 2022 The first demand is harmful to national security and a political hot potato. Matthew Continetti, National Review, 11 June 2022 Many traditional drugstore brands are changing their formulas and crafting non-toxic, natural deodorants that aren’t harmful to your health. Grooming Playbook, The Salt Lake Tribune, 10 June 2022 Some of the most prominent strategies include finding better uses for agricultural subsidies, 86 percent of which go to activities that are harmful to the environment—particularly biodiversity. K.e.d. Coan, Ars Technica, 7 June 2022 See More

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.

First Known Use of harmful

14th century, in the meaning defined above

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Time Traveler for harmful

Time Traveler

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

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Dictionary Entries Near harmful

harmattan

harmful

harmless

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Statistics for harmful

Last Updated

26 Jun 2022

Cite this Entry

“Harmful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harmful. Accessed 3 Jul. 2022.

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More Definitions for harmful

harmful

adjective
harm·​ful | \ ˈhärm-fəl How to pronounce harmful (audio) \

Kids Definition of harmful

: causing or capable of causing harm 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

More from Merriam-Webster on harmful

Nglish: Translation of harmful for Spanish Speakers

Britannica English: Translation of harmful for Arabic Speakers

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