IMPACTION

impingement, impaction

(noun) a sharp collision produced by striking or dashing against something

impaction, impacted tooth

(noun) a disorder in which a tooth is so crowded in its socket that it cannot erupt normally

impaction

(noun) a disorder in which feces are impacted in the lower colon

impaction

(noun) the condition of being pressed closely together and firmly fixed

Source: WordNet® 3.1

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Etymology

Noun

impaction (countable and uncountable, plural impactions)

compression; the packing together of loose matter

something packed together tightly; a mass of densely-packed matter

(medicine) a solid, immobile bulk of stool

(dentistry) Failure of a tooth to erupt into the dental arch, because of adjacent teeth, dense overlying bone, excessive soft tissue, or other factor.

Source: Wiktionary

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Im*pac"tion, n. Etym: [L. impactio a striking : cf. F. impaction.]

1. (Surg.)

Definition: The driving of one fragment of bone into another so that the fragments are not movable upon each other; as, impaction of the skull or of the hip.

2. An immovable packing; (Med.), a lodgment of something in a strait or passage of the body; as, impaction of the fetal head in the strait of the pelvis; impaction of food or feces in the intestines of man or beast.

Source: Webster’s Unabridged Dictionary 1913 Edition

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