BACKGROUND/PURPOSE: This paper investigates the history of pancreas in classical and late antiquity with the intent to correlate it to the modern medical knowledge. Furthermore, an attempt is made to understand the true meaning of the term "kallikreas".METHODS: Only primary textual sources are used in the transcription of ancient references of "pancreas" and/or "kallikreas". All of the references are analyzed and interpreted under a modern prism for better understanding the ancient anatomy proposed.RESULTS: The ancient references describe the actual organ, its position and the blood vessels related to it. An attempt if made to correlate the ancient physiology of the organ to the modern one. Finally, the problematic issue of the ancient terminology is studied.CONCLUSIONS: Textual proofs are offered that the knowledge that exists and that travelled through the ages concerning the identification of pancreas with "kallikreas", from which the hormone kallikrein took its name, is erroneous and that the term refers instead to the mesentery.