The meaning of HARMFUL is of a kind likely to be damaging : injurious. How to use harmful in a sentence.

You do not suppress free speech; you eliminate harmful opinions, obscenity and corruption.

Harmful definition: causing or capable of causing harm; injurious.. See examples of HARMFUL used in a sentence.

Definition of harmful adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

harmful If something is harmful to someone or harmful for them, it has a bad effect on them. Too much salt can be harmful to a young baby. Potassium could be harmful for those with impaired kidneys. …

Something that is harmful has a bad effect on something else, especially on a person's health. ...the harmful effects of smoking.

harm•ful /ˈhɑrmfəl/ adj. causing or capable of causing harm. harm•ful•ly, adv. harm•ful•ness, n. [uncountable] WordReference Random House Unabridged Dictionary of American English © 2025 …

Oct 8, 2025 · Causing or likely to cause harm or damage; injurious. Wear a hat to protect your skin from harmful sunlight. Smoking is harmful to the lungs. Burning fossil fuels is harmful to the environment.

harmful, adj. meanings, etymology, pronunciation and more in the Oxford English Dictionary

Harmful refers to something that is capable of causing damage, injury, or has a detrimental effect on one's health, well-being, or the environment. Harmful is a rock band from Frankfurt, Germany, …