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Related to impaction: inertial impaction, tooth impaction


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′, ĭm′păkt′) im·pact·ed, im·pact·ing, im·pacts
1. To pack firmly together.
2. To strike forcefully: meteorites impacting the lunar surface.
3. 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. See Usage Note below.

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

im·pac′tion n.
Usage Note: Impact in the figurative sense of "a dramatic effect" came under criticism in the 1960s, both as a noun and verb. Complaints that the noun was a pointless hyperbole and a vogue word turned out to be short-lived, and this usage is now is standard: in our 2015 survey, 97 percent of the Usage Panel accepted The program might have a positive impact on our nation's youth. (A similar sentence was accepted by 93 percent of the Panel in 2001.) The verb is a different matter. Many people dislike it because they assume it was converted from the noun in the manner of voguish and bureaucratic words like dialogue 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. Most of the Panelists still disapprove of the intransitive use of the verb meaning "to have an effect": in our 2015 survey, 78 percent of the Panel (down only slightly from 85 percent in 2001) rejected These policies are impacting on our ability to achieve success. The transitive version was once as vilified, but is gradually becoming more acceptable: in 2015, only 50 percent (down from 80 percent in 2001) rejected The court ruling will impact the education of minority students, and only 39 percent (down from 66 percent in 2001) found the literal sense unacceptable in the sentence Thousands of meteors have impacted the lunar surface. Although resistance to the transitive senses is waning, the intransitive use is still strongly disliked and is best avoided. See Usage Notes at contact, impactful.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ɪmˈpæk ʃən)

1. an act or instance of impacting.
2. the state of being impacted.
[1730–40; < Late Latin]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.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
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
crash, smash - the act of colliding with something; "his crash through the window"; "the fullback's smash into the defensive line"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


n. impacción.
1. condición de estar alojado o metido con firmeza en un espacio limitado;
2. impedimento de un órgano o parte.
English-Spanish Medical Dictionary © Farlex 2012


n impactación f; cerumen — tapón de cerumen; dental — inclusión dentaria; fecal — impactación fecal
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in periodicals archive ?
According to the report, the cause of death was recorded as colonic impaction - a blocked colon - and kidney failure.
Impaction is defined as a tooth which is prevented from completely erupting into a normal functional position, due to lack of space, obstruction by another tooth or an abnormal eruption path, inadequate bony length, and insufficient development of the retromolar space with the tooth either partly visible or in communication with the oral cavity or completely invisible.
Faecal impaction should be treated with mineral oil or warm water enemas.
The published data describe the pooled safety across a total of seven clinical studies, where IV meloxicam was evaluated in patients following several types of surgeries, including dental impaction surgery, open abdominal hysterectomy, abdominal laparoscopic surgery, bunionectomy, and abdominoplasty, among others.
Another study by Ahmad et al15 concluded that the prevalence of impacted teeth was high, and there was a predominant for impaction of the mandibular third molars in this study of Al Ahsa Saudi population.
-- Millions of North Americans walk around every day with some degree of ear wax impaction. Every year, 8 million of those people end up at the doctor's office, seeking relief through blockage removal.
The data such as age, sex, mode of presentation, type of foreign body and site of impaction was recorded on a specially designed proforma.
Rigid oesophagoscopy also revealed surrounding erythema, oedema and slough at the site of impaction. The child recovered without any complications and a repeat flexible endoscopy performed at 6 weeks was normal.
The rumen impaction in bovines has emerged as a major clinical problem in Punjab in last few years as a result of multiple factors and particularly ingestion of poor-quality feed.
Conclusion: X-ray was not found to be an ideal modality to diagnose fish or chicken bone impaction in the upper aerodigestive tract.