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 Social media companies use psychologically manipulative algorithms, which are particularly harmful to youth, to seduce users to spend more time on their platforms. Nancy Magee, Orange County Register, 20 Apr. 2024 Elsewhere in the world of harmful deepfakes, two major websites used for creating fake nude images of people are now blocked in the United Kingdom. Dell Cameron Andrew Couts, WIRED, 20 Apr. 2024 For example, the nutrients in fertilizers used on agricultural and residential properties can cause harmful algae blooms, which can impact the safety of drinking water. Jennifer Dixon, Detroit Free Press, 20 Apr. 2024 For Martini Bar, closing even a few hours earlier could be harmful to the business. Devoun Cetoute, Miami Herald, 19 Apr. 2024 Long-term exposure to the sun's harmful ultraviolet (UV) rays, as well as artificial UV rays from sunlamps and tanning beds, causes AKs.19 Symptoms These growths are initially felt rather than seen. Karyn Repinski, Health, 19 Apr. 2024 The prince was due to visit community groups in west London and the neighboring area of Surrey to highlight efforts to reduce food waste as a way to feed people in need and reduce emissions that are harmful to the environment. Patrick Smith, NBC News, 18 Apr. 2024 But experts warn that the broad use of the AI chatbot may amplify problems that have long plagued Meta’s social networks, including harmful misinformation, hate speech and extremist content. Will Oremus, Washington Post, 18 Apr. 2024 In some cases, the influencers, not just on TikTok, but also on Instagram, YouTube, Amazon and other platforms, make money from pitching the skin products that can end up being harmful to young skin. Alexandra Sternlicht, Fortune, 17 Apr. 2024

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 24 Apr. 2024.

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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