like a bolus of saline (anyone who watches TV medical drama knows the word.)
and a bolus is?

it was a clod of earth.. but now it's:

1. A round mass: “A dense bolus of trapped dolphins fills the frame” (Kenneth Browser).
2a. 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 alimentary canal.


from the American Heritage dictionary.

(thanks Jackie.. feisty got me started!)