A hollow or empty space within a solid object, often referring to a natural or artificial opening. noun
The dentist found a cavity in one of my molars.
The bird made its nest in a cavity in the tree.
A decayed part of a tooth caused by bacterial action, leading to a hollow area. noun
Regular brushing can help prevent cavities.
The dentist filled the cavity with a composite resin.
A body cavity, which is a fluid-filled space in a multicellular organism other than those of vessels. noun
The abdominal cavity contains many vital organs.
Surgeons must be careful when operating near the thoracic cavity.