cavity
n. countablen. a hole or an empty space inside something solid. You often hear this word at the dentist when you have a small hole in a tooth.
n. an empty space or hollow area within a solid object or body. In medical contexts, it specifically refers to a hole in a tooth caused by decay or a fluid-filled space in the body.
The dentist found a small cavity in my back tooth.
Engineers discovered a large cavity in the rock that could make the bridge unstable.
The surgeon carefully drained the fluid from the abdominal cavity to relieve the pressure on the patient's internal organs.
From Middle French cavité or Late Latin cavitās, from cav(i) (“hollow, excavated, concave”) + -tās (“-ity”, nominal suffix). First attested in the Mid-16th c.
Commonly used in dentistry to refer to tooth decay or in anatomy to describe internal body spaces.