adjective

harmful

Causing or likely to cause damage or injury.

Breathing this dust is harmful to your lungs over time.

Etymology

The adjective ending describes what produces harm. It covers something that already causes damage and something whose likely effects would be injurious.

More examples

  • Keep harmful chemicals out of children's reach.
  • The treatment can have harmful side effects.
  • Spreading false rumors is harmful to someone's reputation.

Forms

harmful · more harmful · most harmful

harm noun — Damage or injury to someone or something.

Similar words

damaging
Emphasizes actual damage rather than the possibility of injury.
dangerous
Emphasizes the risk of serious injury or loss.
detrimental
Often describes negative effects on progress, health, or success.