harmful

US /ˈhɑːrm.fəl/

UK /ˈhɑːrm.fəl/

1.

causing or likely to cause harm

:

•

Smoking is harmful to your health.

•

Exposure to the sun's UV rays can be harmful.

:

damaging detrimental injurious deleterious pernicious

:

harmless beneficial

:

harm do harm come to harm out of harm's way