| 1. | the striking of one thing against another; forceful contact; collision: The impact of the colliding cars broke the windshield. |
| 2. | an impinging: the impact of light on the eye. |
| 3. | influence; effect: the impact of Einstein on modern physics. |
| 4. | an impacting; forcible impinging: the tremendous impact of the shot. |
| 5. | the force exerted by a new idea, concept, technology, or ideology: the impact of the industrial revolution. |
| 6. | to drive or press closely or firmly into something; pack in. |
| 7. | to fill up; congest; throng: A vast crowd impacted St. Peter's Square. |
| 8. | to collide with; strike forcefully: a rocket designed to impact the planet Mars. |
| 9. | to have an impact or effect on; influence; alter: The decision may impact your whole career. The auto industry will be impacted by the new labor agreements. |
| 10. | to have impact or make contact forcefully: The ball impacted against the bat with a loud noise. |
| 11. | to have an impact or effect: Increased demand will impact on sales. |
im·pact (ĭm'pākt') n.
v. tr.
To have an effect or impact. [From Latin impāctus, past participle of impingere, to push against; see impinge.] im·pac'tion n. Usage Note: The use of impact as a verb meaning "to have an effect" often has a big impact on readers. In our 2001 survey, 85 percent of the Usage Panel disapproved of the construction to impact on, as in the sentence These policies are impacting on our ability to achieve success; fully 80 percent disapproved of the use of impact as a transitive verb in the sentence The court ruling will impact the education of minority students. · It is unclear why this usage provokes such a strong response, but it cannot be because of novelty. Impact has been used as a verb since 1601, when it meant "to fix or pack in," and its modern, figurative use dates from 1935. It may be that its frequent appearance in the jargon-riddled remarks of politicians, military officials, and financial analysts continues to make people suspicious. Nevertheless, the verbal use of impact has become so common in the working language of corporations and institutions that many speakers have begun to regard it as standard. It seems likely, then, that the verb will eventually become as unobjectionable as contact is now, since it will no longer betray any particular pretentiousness on the part of those who use it. See Usage Note at contact. |
impact
in physics, the sudden, forceful coming together in direct contact of two bodies, such as, for example, two billiard balls, a golf club and a ball, a hammer and a nail head, two railroad cars when being coupled together, or a falling object and a floor. Apart from the properties of the materials of the two objects, two factors affect the result of impact: the force and the time during which the objects are in contact. It is a matter of common experience that a hard steel ball dropped on a steel plate will rebound to almost the position from which it was dropped, whereas with a ball of putty or lead there is no rebound. The impact between the steel ball and plate is said to be elastic, and that between the putty or lead balls and plate is inelastic, or plastic; between these extremes there are varying degrees of elasticity and corresponding responses to impact. In a perfectly elastic impact (attained only at the atomic level), none of the kinetic energy of the coacting bodies is lost; in a perfectly plastic impact, the loss of kinetic energy is at a maximum.
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