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Medicine & BodyGreekEnglish

Bolus

/ˈboʊləs/noun

A soft rounded mass, especially of chewed food ready to be swallowed, or a single large dose of a drug given at once.

The Greek roots

βῶλος
bôlos
lump, clod of earth

Literally: a clod

Follow a root:βῶλος1 word

The story of the word

βῶλος was a clod of earth or a lump of anything. Apothecaries borrowed the Latin form for a pill too big to go down comfortably, physiologists gave it to the ball of food the tongue shoves back past the throat, and hospital pharmacy now uses it for a dose delivered in one push rather than by slow drip. Despite the resemblance it has nothing to do with embolus, which comes from a verb meaning to throw in.

How it travelled
Ancient Greek → Late Latin → English
First recorded
16th century

In a sentence

The nurse gave a bolus of saline before starting the infusion.

Chewing works the food into a bolus the tongue can move.

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