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

Examples of bolus in a Sentence

Recent Examples on the Web

Mazlish watched as his wife programmed her insulin pump to deliver both dribbles of basal insulin throughout the day and a large bolus with meals. —Carrie Arnold, Scientific American, 14 Oct. 2025

Within that bolus of bureaucratic bloviation are approximately 280 tax expenditures — also known as loopholes — that can be used by eligible taxpayers to legally reduce their tax burden. —Tor Constantino, Mba, Forbes.com, 2 Apr. 2025

The wearable, fully disposable device provided adjustable basal and bolus insulin for up to three days for people with Type 1 or Type 2 diabetes. —Lance Reynolds, Boston Herald, 5 Dec. 2024

Could infusing an extra bolus of these cells do more harm than good? —Byjennifer Couzin-Frankel, science.org, 14 Nov. 2024

Word History

Etymology

Late Latin, from Greek bōlos lump

First Known Use

1562, in the meaning defined at sense 1

Phrases Containing bolus

• holus-bolus

Rhymes for bolus

• colas
• polis
• solus
• embolus
• gladiolus
• malleolus
• nucleolus

Medical Definition

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