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 And to prevent harmful window collisions, place feeders either within 3 feet of a window or more than 30 feet away. Rita Pelczar, Better Homes & Gardens, 19 Jan. 2022 But civil rights advocates almost uniformly consider the new state voting laws harmful to minority participation. Ronald Brownstein, CNN, 18 Jan. 2022 Fish consumption advisories have been issued across the state for a number of harmful contaminants. Laura Schulte, Milwaukee Journal Sentinel, 18 Jan. 2022 When someone in a larger body restricts their eating in a harmful way, it may be diagnosed as atypical anorexia. Macaela Mackenzie, SELF, 18 Jan. 2022 O’Malley imported two commissioners from New York City, and the report describes the tenure of Commissioner Kevin Clark as disastrous, rife with turmoil and the implementation of harmful policies. Justin Fenton, baltimoresun.com, 13 Jan. 2022 Family Services previously launched two investigations into Damari's family prior to his death, according to local reports – including one in which his mother was accused of making harmful threats, an allegation later ruled unfounded. Michael Ruiz, Fox News, 12 Jan. 2022 Anything less almost guarantees their efforts will be folded into, and even used to optimize or disguise, the harmful impacts of Big Tech’s products. Elena Maris, Wired, 12 Jan. 2022 The company was also worried that the foam could emit harmful gases, which along with the particles could be carcinogenic. Denise Roland, WSJ, 12 Jan. 2022

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

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Last Updated

21 Jan 2022

Cite this Entry

“Harmful.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harmful. Accessed 27 Jan. 2022.

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More Definitions for harmful



English Language Learners Definition of harmful

: causing or capable of causing damage or harm


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



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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