Here are some examples of how it's used:
* Pericarditis: Inflammation of the pericardium, the sac surrounding the heart.
* Periosteum: The membrane that surrounds bone.
* Perineum: The area between the anus and the genitals.
* Peripheral: Relating to the outer limits of the body or an organ.
Keep in mind that while "peri-" often means "surrounding," its exact meaning can vary slightly depending on the context.