n. pl. bo·lus·es
1. A round mass: "A dense bolus of trapped dolphins fills the frame" (Kenneth Browser).
a. A single, relatively large quantity of a substance, such as a dose of a drug, intended for therapeutic use and taken orally.
b. A concentrated mass of a substance administered intravenously for diagnostic or therapeutic purposes.
3. A soft mass of chewed food within the mouth or digestive tract.
[Medieval Latin bōlus, from Greek bōlos, lump of earth.]
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