Absorbed dose is the amount of energy from ionizing radiation absorbed per unit mass of matter, expressed in Gray units.

Abrasivity is the property of one material to wear away another material by means of frictional contact.

Abrasive is a substance used for abrading, smoothing, or polishing. Abrasive is tending to abrade. It is causing irritation—abrasively adv, abrasiveness n

Abrasion is the wearing away of a substance or structure (such as the skin or the teeth) through some unusual or abnormal mechanical process. Abrasion is an abnormal wearing away of the tooth substance...

Abrade is to rub away the external covering or layer of a part—comp ATTRITION, EROSION

Ablation is the separation or detachment; extirpation; eradication. Ablation is removal of a part, especially by cutting.

Abfraction is the pathologic loss of hard tooth substance caused by biomechanical loading forces. Such loss is thought to be due to flexure and chemical fatigue degradation of enamel and/or dentin at some location...

Aberrant is a deviation from the normal or usual course, form, or location. It is the straying from the normal way.

Abduct is to draw away from the median plane.

Abbe flap is an eponym for a lip switch operation. A triangular, full thickness flap from the lower lip used to fill in a deficit in the upper lip. Specifically applied to the midportion...