Most bones consist of two types of bone: the cortical bone is the hard smooth bone on the outside and the cancellous bone is on the inside. The cancellous bone is spongey and fibrous and fills the medulla cavity of the bone. So yes, they do have a filled cavity, but it's most evident in long bones like the femur or humerus.
The cavity between bones at the joint is known as the synovial cavity. This space is filled with synovial fluid, which helps to reduce friction and facilitate smooth movement of the bones at the joint.
medullary cavaities are found deep in the diphysis of long bones and are filled with yellow marrow in the adult
An air-filled bony cavity is a hollow space within a bone that contains air. These cavities are found in certain bones like the sinuses of the skull, where they help to reduce the weight of the bone and resonate sound.
The medical term is "paranasal sinuses." These are air-filled cavities located within the bones surrounding the nasal cavity. They are important for natural drainage and humidifying the air we breathe.
A synovial joint has a fluid-filled cavity known as the synovial cavity, which contains synovial fluid. This fluid helps to reduce friction between the bones, nourish the joint, and provide lubrication for smooth movement.
A blastocoele is the fluid-filled cavity in the blastula.
In the bones of the body. Bones have a swollen part on both the ends called epiphysis and in between epiphysis is diaphysis. when a TS is taken through diaphysis a central cavity is seen called marrow cavity which is filled with Yellow bone marrow.
Medullary cavity (because bones like feet are short bones and they have the cavity)
Spinal cavity
The middle ear is a small, air-filled cavity behind the tympanum consisting of epithelial (skin) cells. It is filled with the auditory ossicles, the smallest bones in the dog's body.
The hollow part of bones are mostly filled with Red Marrow
a joint cavity, the potential space bounded by the synovial membrane and articular cartilages of all synovial joints. Normally, the articular cavity contains only sufficient synovial fluid to lubricate the internal surfaces.