harmful

play
adjective harm·ful \ˈhärm-fəl\

Definition of harmful

  1. :  of a kind likely to be damaging :  injurious

harmfully

play \ˈhärm-fə-lē\ adverb

harmfulness

noun

Examples of harmful in a Sentence

  1. DDT has been proven to be extremely harmful to the environment.

Recent Examples of harmful from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'harmful'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of harmful

14th century


HARMFUL Defined for English Language Learners

harmful

play
adjective

Definition of harmful for English Language Learners

  • : causing or capable of causing damage or harm


HARMFUL Defined for Kids

harmful

play
adjective harm·ful \ˈhärm-fəl\

Definition of harmful for Students

  1. :  causing or capable of causing harm :  injurious Keep harmful substances away from children.

harmfully

\-fə-lē\ adverb

Law Dictionary

harmful

adjective harm·ful

Legal Definition of harmful

  1. :  of a kind likely to cause harm

harmfully

adverb

harmfulness

noun


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