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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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 People should avoid any social media challenge asking them to take medicines, whether prescription or over the counter, or to partake in other potentially harmful activities. — Katia Hetter, CNN, 5 Mar. 2025 Aside from shower head filters, a clarifying shampoo is the ultimate solution to combating build-up on your scalp caused by natural oil production (or perhaps worsened by poor water quality rich in harmful minerals). — Arden Fanning Andrews, Vogue, 4 Mar. 2025 If left sitting out for too long, harmful bacteria such as E.Coli, listeria, and salmonella can grow and pose a serious risk to your furry friend. — Mary Cornetta, Better Homes & Gardens, 4 Mar. 2025 Studies have shown that testers can harbor harmful bacteria, including Staphylococcus aureus (a common cause of styes and other infections), E. coli, yeast, and mold. — Mark Joseph, Newsweek, 24 Feb. 2025 See All Example Sentences for harmful
Recent Examples of Synonyms for harmful
  1. detrimental
  2. damaging
  3. dangerous
  4. adverse
  5. bad
Adjective
  • In addition to losing the benefits for our kids, this loss of funds is a huge blow to community farmers and ranchers and is detrimental to school meal programs struggling to manage rising food and labor costs.
    — Khaleda Rahman, Newsweek, 13 Mar. 2025
  • Musk’s Twitter purchase was a bad deal financially and has been detrimental to X’s bottom line, but his ownership of the platform helped boost his cultural and political relevance by keeping him in the center of the news cycle.
    — Charlie Warzel, The Atlantic, 12 Mar. 2025
Definition of detrimental
Adjective
  • The cyclone was already bringing heavy rainfall to coastal areas on Saturday, along with damaging winds and storm surges.
    — Hilary Whiteman, CNN, 7 Mar. 2025
  • The system brought the potential for heavy rain, damaging winds, and isolated tornadoes.
    — Russel Honoré, Newsweek, 5 Mar. 2025
Definition of damaging
Adjective
  • Paved highways meant dangerous going for horse and rider, and her only mishap of the trip would come at Portland, when Goldie slipped on rain-slick pavement and fell on his rider and broke her leg, resulting in a delay of several weeks.
    — Ben East, Outdoor Life, 14 Mar. 2025
  • Part of this season’s focus has been on building his partnership with Murphy, whose primary attacking role is to find Isak in dangerous areas, and encouraging his team-mates to involve the striker whenever possible.
    — Chris Waugh, The Athletic, 14 Mar. 2025
Definition of dangerous
Adjective
  • When ingested or inhaled, these microplastics can release these chemicals into the body, potentially leading to adverse health effects.
    — Sheah Rarback, Miami Herald, 13 Mar. 2025
  • Research shows that supplementing with 0.14 to 0.36 grams per pound of body weight for up to five years is associated with minimal adverse effects and health risks.
    — Melissa Nieves, Verywell Health, 13 Mar. 2025
Definition of adverse
Adjective
  • Jayson Tatum kept the Celtics in the game most of the night with 33 points, eight assists and eight rebounds, but Brown had one of his worst games of the year with just 10 points.
    — Jay King, The Athletic, 13 Mar. 2025
  • How to build good habits and break bad ones via tiny changes in behavior. … Paperback fiction 1.
    — The California Independent Booksellers Alliance, Los Angeles Times, 12 Mar. 2025
Definition of bad

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“Harmful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/harmful. Accessed 17 Mar. 2025.

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