a. The striking of one body against another; collision. See Synonyms at collision.
b. The force transmitted by a collision.
2. The effect or impression of one person or thing on another: still gauging the impact of automation on the lives of factory workers.
v. (ĭm-păkt, ĭmpăkt′) im·pact·ed, im·pact·ing, im·pacts
1. To pack firmly together.
2. To strike forcefully: meteorites impacting the lunar surface.
3. Usage Problem To have an effect or impact on: "No region ... has been more impacted by emerging ... economic trends" (Joel Kotkin).
To have an effect or impact.
[From Latin impāctus, past participle of impingere, to push against; see IMPINGE.]
Usage Note: Impact came under criticism in the 1960s for its use both as a noun and verb, at least in the figurative use describing a dramatic influence or effect. The noun was criticized as a pointless hyperbole and as a vogue word. But complaints about the noun were not long-lived, and this usage has firmly established itself as standard. In our 2001 survey, 93 percent of the Usage Panel accepted the noun in the sentence The program might have a positive moral impact on inner-city youth. But the verb is a different matter and ranks among the most detested of English usages. Many people assume that popular distaste for the verb results from its conversion from the noun, in the manner of voguish and bureaucratic words like leverage and interface. But in fact impact was a verb long before it was a noun (the verb dates from the early 1600s; the noun from the late 1700s). Nor can the animosity to the figurative use of the verb stem from its novelty in the 1960s, since this use dates from the 1930s, allowing plenty of time for people to grow accustomed to it. Whatever the reason, a large majority of the Usage Panel has disapproved of the use of the verb meaning "to have an effect" since the early 1980s. Even in our 2001 survey, 85 percent of the Panel rejected the intransitive use in the sentence These policies are impacting on our ability to achieve success, and 80 percent rejected the transitive use in the sentence The court ruling will impact the education of minority students. Even the literal use of the verb was found unacceptable by a majority of the Panel (66 percent) in 2001 in the sentence Thousands of meteors have impacted the lunar surface. See Usage Note at contact.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2014 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.
American Heritage Dictionary Products
The American Heritage Dictionary, 5th Edition
The American Heritage Dictionary of Idioms
The American Heritage Roget's Thesaurus
Curious George's Dictionary
The American Heritage Children's Dictionary
The American Heritage Dictionary of Indo-European Roots
The American Heritage Student Grammar Dictionary
The American Heritage Desk Dictionary + Thesaurus
The American Heritage Science Dictionary
The American Heritage Dictionary of Business Terms
The American Heritage Student Dictionary
The American Heritage Essential Student Thesaurus