harmful
adj.adj. causing damage or injury to someone or something. You use this to describe things that are bad for your health, the environment, or your success.
adj. causing or capable of causing physical, emotional, or environmental damage. Often used to describe substances, behaviors, or influences that have a negative impact on a subject.
Smoking is harmful to your health.
The factory was fined for releasing harmful chemicals into the local river system.
While some critics argue that the new policy is beneficial, others maintain that its long-term effects will be harmful to the country's economic stability.
From Middle English harmful, from Old English *hearmful (suggested by hearmfullīċ (“harmful; hurtful”)), equivalent to harm + -ful. Cognate with German harmvoll, Danish harmfuld, Swedish harmfull.
Typically followed by the preposition 'to' when specifying the object being damaged.