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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Cleaning is a necessary part of life, an essential task that keeps us (and our families) safe from harmful germs and bacteria. Alyssa Shaffer, Better Homes & Gardens, 23 Nov. 2024 Third-party testing confirms that the supplement contains the ingredients listed on the label and is free from harmful contaminants. Barbie Cervoni, Health, 23 Nov. 2024 Just be sure never to mix vinegar with hydrogen peroxide, which can cause a harmful toxic gas if inhaled. Rebecca Jones, Southern Living, 23 Nov. 2024 Some companies have reportedly dealt with safety issues, like bad actors who abuse the model to give harmful advice or prey on vulnerable people. Jamie Ducharme, TIME, 22 Nov. 2024 See all Example Sentences for harmful 

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 1 Dec. 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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