- causing or capable of causing harm; injurious: a harmful idea; a harmful habit.
Origin of harmful
SynonymsSee more synonyms on Thesaurus.com
hurtful, detrimental, damaging, deleterious.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for harmful
So why are we continually inundated with images and hate speech perpetuating this harmful lie?Can We Lose the Violent Muslim Cliché?
October 12, 2014
It will likely be harmful to the reputations of both the president and vice president.Exposed: The White House’s Professor-in-Chief
October 8, 2014
Another act, however, may be considered immoral not because it is harmful but because it evinces disloyalty.It’s Official: Religion Doesn’t Make You More Moral
September 23, 2014
From a pediatric ICU in Melbourne, Australia, to an elevator in Brooklyn, we see just how harmful refusing to vaccinate can be.Hey Anti-Vaxxers, Watch NOVA: Vaccines--Calling the Shots
September 11, 2014
Studies revealed that exposure to harmful UV rays could cause wrinkles and other signs of aging, as well as skin cancer.Is the Facekini the Future of Beachwear?
August 23, 2014
Corporal punishment of schoolboys is only useless and harmful brutality.
These are the persons who do the most harm in society, and introduce into it the most harmful taints.
Dirt, in the ordinary sense of the word, is not harmful to a sound skin.The Meaning of Evolution
Samuel Christian Schmucker
What other wild animals or harmful insects have you on this planet?
Usually we think of explosions as harmful, and they often are, of course.Common Science
Carleton W. Washburne
- causing or tending to cause harm; injurious
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for harmful
Online Etymology Dictionary, © 2010 Douglas Harper