harmful

adjective

ˈhärm-fəl How to pronounce harmful (audio)
Definition of harmfulnext
as in detrimental
causing or capable of causing harm DDT has been proven to be extremely harmful to the environment

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of harmful The video is supposed to be a critique of the harmful way women are judged for their appearance. — Martha Ross, Mercury News, 3 Aug. 2026 Cold water can increase blood flow to your face, boosting your skin’s protection from free radicals, harmful compounds caused by exposure to UV light and pollution. — Sherri Gordon, HEALTH, 3 Aug. 2026 The administration argues that the new tariffs are necessary to address Canada’s harmful discrimination against the United States auto industry, and are justified by Section 338 of Smoot-Hawley. — Caleb Petitt, Fortune, 2 Aug. 2026 These organisms, when introduced to other ecosystems, can cause a wide array of consequences, from outcompeting native species to damaging infrastructure to introducing pathogens harmful to marine life and, sometimes, humans. — Christopher Cann, USA Today, 2 Aug. 2026 See All Example Sentences for harmful
Recent Examples of Synonyms for harmful
  1. detrimental
  2. damaging
  3. dangerous
  4. adverse
  5. bad
Adjective
  • Those children were held in custody for an average of 194 days before being released to sponsors, which lawyers who represent the children say is unusually long and has been detrimental to the health and safety of the children.
    — Chiara Eisner, NPR, 1 Aug. 2026
  • Much has been made of the detrimental effects of the rise in the minimum wage and an increase in employers’ national insurance costs (effectively a tax on employment) introduced by former Chancellor of the Exchequer Rachel Reeves.
    — Roger Trapp, Forbes.com, 31 July 2026
Definition of detrimental
Adjective
  • Several rounds of showers and thunderstorms are expected Wednesday into Thursday morning, with a few storms capable of damaging winds and heavy downpours, the National Weather Service said.
    — Kansas City Star, Kansas City Star, 5 Aug. 2026
  • A couple of those storms could become severe, with damaging winds and torrential downpours.
    — Rachael Jay, CBS News, 5 Aug. 2026
Definition of damaging
Adjective
  • Despite Penta's aggressive offense and dangerous maneuvers, Gable persevered, ultimately making Penta submit with a decisive ankle lock, securing a triumphant and emotional victory.
    — Alfred Konuwa, Forbes.com, 3 Aug. 2026
  • Three wildfires are burning in Spokane County, Washington, and thousands of families have been ordered to flee their homes overnight, as state officials warn of an incredibly dangerous situation and brace for what daylight may reveal.
    — Martin Goillandeau, CNN Money, 2 Aug. 2026
Definition of dangerous
Adjective
  • The adverse weather in Auckland limited the group’s freedom to explore, but there were no such constraints in Sydney’s winter sun.
    — Elias Burke, New York Times, 2 Aug. 2026
  • Islamabad — Rescuers searching for 10 climbers missing after an avalanche on Pakistan's Broad Peak located four bodies Friday and were continuing to search for the others despite adverse weather that hampered helicopter flights, officials said.
    — CBS News, CBS News, 31 July 2026
Definition of adverse
Adjective
  • The last war, which began in 2014, left Yemen facing one of the world’s worst humanitarian crises.
    — Sophia Saifi, CNN Money, 7 Aug. 2026
  • Even worse, Brooks directed him to contact his agent instead.
    — Tom Smyth, Vulture, 6 Aug. 2026
Definition of bad

Browse Nearby Words

harmers
harmful
harmfulness
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Cite this Entry

“Harmful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/harmful. Accessed 8 Aug. 2026.

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Nglish: Translation of harmful for Spanish Speakers

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