Wiktionary
barium meal
n. 1 (context medicine English) A preparation of barium sulfate (a radioopaque compound) which the patient ingests for the purpose of producing clear radiographs of the esophagus, stomach(,) and duodenum. 2 Short for "barium meal radiography", a medical examination procedure based on observing barium meal's progress in the digestive tract.
Usage examples of "barium meal".
Later, when it comes back to me it provides an interesting road map of data transfer, a barium meal, revealing who squeals and to whom.