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 The unique design and structure make this wire creation sturdy — and sometimes harmful to the touch. Brittany Kasko, Fox News, 24 Nov. 2023 It's believed that the fire released the potentially harmful gas sulfur dioxide, but officials have not released results of measurements taken from air monitoring equipment that were deployed Wednesday night. CBS News, 23 Nov. 2023 The symptoms of seasonal allergies occur when your child's immune system identifies environmental triggers as harmful invaders. Emily Shiffer, Parents, 22 Nov. 2023 Pepsi’s commitment to featuring diverse individuals in their advertising not only promotes inclusivity but also challenges harmful stereotypes, fostering a more positive and accepting societal attitude. Steve Simoncic, Rolling Stone, 21 Nov. 2023 What keeps him up at night: eco events that hand out plastic water bottles; compost sites that produce harmful runoff but look great in their Instagram feeds; his own dependence on fossil fuels to carry equipment. John Leland, New York Times, 19 Nov. 2023 So while it’s not considered harmful, there are a couple of ways to prevent these black dots from popping up if their appearance bothers you. Audrey Noble, Vogue, 19 Nov. 2023 It’s become so widely viewed as not harmful, a recent Pew Research poll found that 9 in 10 Americans believe marijuana should be legal for both medicinal and recreational use. Akshay Syal, M.d., NBC News, 18 Nov. 2023 While these can potentially become harmful, in most cases parasocial interactions are a source of escape, fun and fantasy. Angeline Close Scheinbaum, The Conversation, 17 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'harmful.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 28 Nov. 2023.

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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