Synonyms of harmful in English:

harmful


See definition of harmful

adjective

1‘the harmful effects of cigarette smoking’

SYNONYMS
damaging, injurious, detrimental, dangerous, deleterious, unfavourable, negative, disadvantageous, unhealthy, unwholesome, hurtful, baleful, wounding, destructive, environmentally unfriendly
noxious, hazardous, poisonous, toxic, deadly, lethal
bad, evil, malign, malignant, malevolent, corrupting, subversive, pernicious
rare baneful, maleficent, malefic
ANTONYMS

beneficial, harmless