Having a significant or powerful effect.
Usage Note: The word impactful rankles many people. Even though the -ful suffix was historically productive, yielding helpful words like eventful, bountiful, wonderful, and helpful itself, many view impactful as an affront to the English language, perhaps because of its association with the jargon of advertising and business. In our 2015 survey, 77 percent of the Usage Panel found the sentence This software will allow you to create impactful and original imagery to be unacceptable. Using this word in your speech and writing will be undoubtedly have a great impact, but probably not in the way you'd like.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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