What does the prefix "peri-" mean in medical terms?

The prefix "peri-" in medical terminology is commonly used to indicate a position that is around or surrounding a particular structure or organ. This prefix derives from the Greek word "peri," which directly translates to "around" or "surrounding." For example, in terms like "perioperative," it describes events or conditions that occur around the time of surgery, and "pericardium" refers to the membrane surrounding the heart. Thus, the meaning of "around" is essential in various medical contexts to describe not just physical positioning, but also relationships between structures in anatomy and pathology.