Sinus

A cavity or hollow space in a bone or other tissue such as the air‐filled paranasal sinuses or dilated channels for venous blood in the cranium or liver.

Recess between the teeth or lobes of a margin;

Angle formed by the basal lobes of a leaf.

The cleft between two lobes or segments of a leaf.

The recess between two parts of an organ.

A channel for the passage of blood.

A cavity inside the body, including the cavities inside the head behind the cheekbone, forehead and nose.

A tract or passage which develops between an infected place where pus has gathered and the surface of the skin.

A wide venous blood space.

Air cavity within a bone, especially the nasal sinuses in the bones of the face and skull.

A cavity or channel, usually within a bone, such as the air-containing spaces in the bones of the nose, lined with mucous membranes. There are numerous sinuses in the bones of the skull.

An air cavity within a bone, especially any of the cavities within the bones of the face or skull.

A term applied to narrow cavities of various kinds, occurring naturally in the body, or resulting from disease. Thus it is applied to the air-containing cavities which are found in the frontal, ethmoidal, sphenoidal and maxillary bones of the skull, and which communicate with the nose. The function of these paranasal sinuses, as they are known, is doubtful, but they do lighten the skull and add resonance to the voice. They enlarge considerably around puberty and in this way are a factor in the alteration of the size and shape of the face. The term is also used in connection with the wide spaces through which the blood circulates in the membranes (meninges) of the brain. Cavities which are produced when an abscess has burst, but remain unhealed, are also known as sinuses.

One of the hollow spaces above the nose that are lined with mucous membranes.

In wound management, a sinus tract refers to a slender, hollow channel within the body that extends from an infected area to the skin’s surface. This tunnel-like structure allows for the drainage of fluids, pus, or other materials from an infected or inflamed site, providing a pathway for them to exit the body. Sinus tracts can be a notable feature in certain types of wounds, serving as a means of facilitating healing and alleviating infection-related complications.