1. <pharmacology> A quantity to be administered at one time, such as a specified amount of medication.

2. <radiobiology> A general term denoting the quantity of radiation or energy absorbed. For special purposes it must be appropriately qualified. If unqualified, it refers to absorbed dose. Unit of absorbed dose is the rad. The SI unit is the gray (1 Gy = 1 J kg-1 = 100 R).

Origin: Gr. Dosis = a giving

(16 Dec 1997)