SINCE 1828

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bolus

noun bo·lus \ ˈbō-ləs \

plural boluses

1 : a rounded mass: such as

a : a large pill

b : a soft mass of chewed food

2 medical

a : a dose of a substance (such as a drug) given intravenously

b : a large dose of a substance given by injection for the purpose of rapidly achieving the needed therapeutic concentration in the bloodstream

Recent Examples of bolus from the Web

But true mastery of the subject requires not only a big bolus of math and physics but a whopping expansion of one’s inner vision.

— alan hirshfeld, WSJ, "The Greatest Show on Earth," 11 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'bolus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of bolus

Late Latin, from Greek bōlos lump

NEW! Time Traveler

First Known Use: 1562

See Words from the same year

Other Pharmacology Terms

anodyne, cathartic, emetic, emollient, liniment, paregoric, poultice, purgative, soporific, spectrum

Medical Dictionary

bolus

noun bo·lus \ ˈbō-ləs \

plural boluses

1 : a rounded mass: as

a : a large pill

b : a soft mass of chewed food

2 a : a dose of a substance (as a drug) given intravenously

b : a large dose of a substance given by injection for the purpose of rapidly achieving the needed therapeutic concentration in the bloodstream

the patient receives a bolus dose to reach the minimum effective analgesic concentration
—J. F. Camp

subcutaneous injection of a premeal bolus of fast-acting insulin

Learn More about bolus

See words that rhyme with bolus Nglish: Translation of bolus for Spanish speakers Britannica.com: Encyclopedia article about bolus

Seen and Heard

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