The term pericardiac refers to anything related to the pericardium, which is the protective sac surrounding the heart. There are several synonyms for pericardiac, which can be useful in medical and scientific writing. Some of these include pericardial, cardiac sac, and epicardial. The pericardium also has layers, and each has its own specific name. The outer layer is called the fibrous pericardium, and the inner layer is the serous pericardium. The serous pericardium has two layers, the parietal and the visceral. When discussing the pericardium, it is important to use accurate terminology and clear synonyms to avoid confusion.