Definition from Wiktionary, the free dictionary
- Rhymes: -ækʃən
impaction (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.