A hollow area within the body.
A hole or hollow depression in a solid object.
A small or large hole in a tooth caused by caries; often also a soft area adjacent to the hole also affected by caries.
The outer layer of an internal organ or body structure, such as the kidney or the brain.
The tissue of a stem or root that lies inward from the epidermis, but exterior to the vascular tissue.
The outer surface of a piece of flint.