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 Douglas claims the company failed to use safe food storage, handling and preparation practices, failed to inspect food and kitchen conditions for contamination and failed to eliminate harmful bacteria before serving the meal. — Anthony Thompson, USA Today, 25 Aug. 2026 Focus on an actual harmful person, not the guy who everyone in Hollywood knows is hyper-intelligent, empathetic and talented. — Tommy McArdle, PEOPLE, 24 Aug. 2026 Michael Harte, 54, of Terryville, has been arrested and charged on a warrant with harmful communication with a minor, according to the Naugatuck Police Department. — Stephen Underwood, Hartford Courant, 23 Aug. 2026 Pests or salt buildup in soil can stress pothos; use insecticidal soap or flush or replace soil to remove harmful deposits. — Andy Wilcox, Better Homes & Gardens, 22 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
  • New redistricting maps There’s also the detrimental effects for Democrats of recent redistricting in Florida.
    — Joshua Ceballos, Miami Herald, 22 Aug. 2026
  • The math curriculum, in my view, has been detrimental to many students.
    — Olivia Young, CBS News, 21 Aug. 2026
Definition of detrimental
Adjective
  • Missing, say, 30 games would likely not be as damaging as missing half a season, or a whole season.
    — Evan Drellich, New York Times, 26 Aug. 2026
  • Strong El Niño events, such as the one revving up in the tropical Pacific, have rarely spared the Golden State from significant and damaging consequences.
    — Andrew Freedman, CNN Money, 25 Aug. 2026
Definition of damaging
Adjective
  • The desert’s location on the southern border has led to many migrants attempting to cross it by using dangerous backcountry routes, the experts said.
    — Emma Tucker, CNN Money, 24 Aug. 2026
  • Rather, this is a dangerous, shape-shifting synthetic entity that ravaged their entire planet.
    — Siddhant Adlakha, Vulture, 24 Aug. 2026
Definition of dangerous
Adjective
  • Then England attracted adverse attention for openly drinking in the Queensland resort of Noosa when 2-0 down in a one-sided Ashes series in Australia.
    — Paul Newman, New York Times, 23 Aug. 2026
  • Women with high occupational heat exposure were roughly twice as likely to suffer a miscarriage or stillbirth as those working in cooler conditions, and faced elevated risks of adverse birth outcomes overall.
    — Catarina Rolfsdotter-Jansson, Forbes.com, 22 Aug. 2026
Definition of adverse
Adjective
  • Poor Anton has been left out of the drama all day, an effort by Billie and Samir to prevent an already bad futzing from escalating to something severe, and that’s never where Anton likes to be.
    — Ben Rosenstock, Vulture, 28 Aug. 2026
  • Although rarely seen, its reemergence earlier this summer is a signal of how bad the region’s ongoing drought has gotten, as well as a warning for the difficult months ahead.
    — Andrew Paul, Popular Science, 27 Aug. 2026
Definition of bad

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Cite this Entry

“Harmful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/harmful. Accessed 28 Aug. 2026.

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