bolus
/ˈbəʊləs/noun
(pl. boluses)
1- a small rounded mass of a substance, especially of chewed food at the moment of swallowing块, 团（尤指咀嚼后准备下咽的食物）。
1.1
- a type of large pill used in veterinary medicine（兽医用的）大丸药。
1.2
- Medicine a single dose of drug or other medicinal preparation given all at once【医】一剂药。
词源
mid 16th cent. (denoting a large pill of medicine)： via late Latin from Greek bōlos 'clod'.