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 What content creators often fail to mention are the harmful risks associated with consuming liver cleanse supplements. Caroline C. Boyle, USA TODAY, 27 Sep. 2024 This new agency was created to promote consumer protection and eliminate harmful anti-competitive business practices. The Arizona Republic, 27 Sep. 2024 The lingering toxins in Chickasaw Park pond Since at least the 1990s, sampling showed the presence of harmful toxins in the Chickasaw Park pond’s fish population, including dioxins and heavy metals. Connor Giffin, The Courier-Journal, 26 Sep. 2024 As an antioxidant, vitamin C may also help reduce the number of free radicals harmful to bones.9 Anti-inflammatory effects: Bromelain is well-known as an anti-inflammatory agent. Brittany Lubeck, Ms, Rdn, Verywell Health, 26 Sep. 2024 See all Example Sentences for harmful 

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 9 Oct. 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

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