Definition of 'harmful'

Adjective

1. injurious to physical or mental health; "noxious chemical wastes"; "noxious ideas"
      Synonyms: noxious
      Antonyms: innocuous harmless
2. able or likely to do harm
3. causing or capable of causing harm; "too much sun is harmful to the skin"; "harmful effects of smoking"
      Antonyms: harmless
4. constituting a disadvantage
      Synonyms: disadvantageous
      Antonyms: advantageous
5. contrary to your interests or welfare; "adverse circumstances"; "made a place for themselves under the most untoward conditions"
      Synonyms: adverse inauspicious untoward
6. tending to cause great harm
      Synonyms: evil injurious

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