| Term | Definition |
| Peritoneum | Membrane surrounding the organs in the abdomen |
| Pleura | Membrane surrounding the lungs |
| Mediastinum | Space between the lungs, containing the heart |
| Abdominal cavity | Space containing the liver, gallbladder, and stomach; also called abdomen |
| Cranial cavity | Space within the skull, containing the brain |
| Pelvic cavity | Space below the abdominal cavity, containing the urinary bladder |
| Thoracic cavity | Entire chest cavity, containing the lungs, heart, trachea, esophagus, and bronchial tubes |
| Diaphragm | Muscle between the thoracic cavity, and abdominal cavities |
| Pelvis | Bones of the hip |
| Spinal cavity | Space within the backbones, containing the spinal cord |