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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.


(ɪmˈpæk ʃən)

1. an act or instance of impacting.
2. the state of being impacted.
[1730–40; < Late Latin]
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"


n. impacción.
1. condición de estar alojado o metido con firmeza en un espacio limitado;
2. impedimento de un órgano o parte.


n impactación f; cerumen — tapón de cerumen; dental — inclusión dentaria; fecal — impactación fecal
References in periodicals archive ?
His X-ray the same afternoon revealed residual impaction and mild displacement of bony fragments with extension of fracture into joint line with mild residual middle inter-phalangeal joint subluxation.
This procedure, called diastema, stops food impaction within the front teeth and gums and prevents the need for tooth extraction later in life.
These glands have a multitude of functions and can develop a variety of conditions including impaction, rupture, adenitis, squamous metaplasia, and neoplasia of various types, with squamous cell carcinoma the most commonly reported.
Ingesting or aspirating a foreign body can result in impaction in the pharynx or larynx, with an estimated prevalence of 13/100,000; surgical management is required in less than 1% of cases.
Horses may develop impaction, which is a blockage within the gastrointestinal tract.
Reusable laryngeal mask, fins of protecting against the epiglottis faecal impaction, loose not intercalating drain, size 1.
The core technology unifies DC impaction (triboelectric) and AC induction electrostatic signals superior accuracy, reliability and repeatability.
It may lead to faecal impaction, in which liquid faeces may leak around impacted ones.
Faecal impaction can affect up to 50 per cent of older adults in hospital wards or care homes and can lead to faecal incontinence.
Cystic fibrosis is a chronic disease characterized by progressive loss of pulmonary function due to infection and mucus impaction leading to destruction of the conductive airways and lung parenchyma.
The resultant pain, in most cases, is due to strains and possible tears to surrounding muscles, tendons and ligaments of the neck as well is impaction of the lower vertebrae in the cervical (neck) spine (most commonly at C5 and C6 spinal level).
He said: "Since the better weather arrived, we have been presented with a dozen cases of gut impaction following ingestion of seaweed.