bolus
[bo´lus] 1. a rounded mass of food or pharmaceutical preparation ready to be swallowed, or such a mass passing through the gastrointestinal tract.
2. a concentrated mass of pharmaceutical preparation, e.g., an opaque contrast medium, given intravenously or swallowed.
3. a mass of scattering material, such as wax or paraffin, placed between the radiation source and the skin to achieve a precalculated isodose pattern in the tissue irradiated.
alimentary bolus the mass of food, made ready by mastication, that enters the esophagus at one swallow.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.