Impaction

im·pact  (mpkt)

n.

1. The striking of one body against another; collision. See Synonyms at collision.

2. The force or impetus transmitted by a collision.

3. The effect or impression of one thing on another: still gauging the impact of automation on the lives of factory workers.

4. The power of making a strong, immediate impression: a speech that lacked impact.

v. (m-pkt) im·pact·ed, im·pact·ing, im·pacts

v.tr.

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 demographic and economic trends" (Joel Kotkin).

v.intr. Usage Problem

To have an effect or impact.

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[From Latin impctus, past participle of impingere, to push against; see impinge.]

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im·paction 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.

Thesaurus

Noun	1.	impaction - the condition of being pressed closely together and firmly fixed condition, status - a state at a particular time; "a condition (or state) of disrepair"; "the current status of the arms negotiations"
	2.	impaction - a disorder in which feces are impacted in the lower colon disorder, upset - a physical condition in which there is a disturbance of normal functioning; "the doctor prescribed some medicine for the disorder"; "everyone gets stomach upsets from time to time"
	3.	impaction - a disorder in which a tooth is so crowded in its socket that it cannot erupt normally impacted tooth disorder, upset - a physical condition in which there is a disturbance of normal functioning; "the doctor prescribed some medicine for the disorder"; "everyone gets stomach upsets from time to time"
	4.	impaction - a sharp collision produced by striking or dashing against something impingement crash, smash - the act of colliding with something; "his crash through the window"; "the fullback's smash into the defensive line"