sinus

(si’nus) [L. for “cavity,” ‘“ bosom,” etc.]. 1. A rece , cavity, or hollow space. 2. A dilated channel for venous blood: found chiefly within the cranium. 3. An air-cavity in one of the cranial bones; especially one communicating with the nose. Such are the ethmoid, frontal, maxillary, and sphenoid sinuses. 4. Ἂ suppurating channel or fistula. air-8., a cavity in a bone containing air. s. of the anterior chamber, the narrow space at the edge of the anterior chamber of the eye, between the border of the cornea and the root of the iris. aortic s., a pouch-like dilatation of the aorta, opposite each of the segments of the semilunar valve. Arlt’s 8., a small rece occasionally seen in the lower part of the lacrimal sac. auricular s. Same as Sinus tenosus (1). basilar s. Same as transverse s. Breschet’s s., the sphenoparietal sinus. Β. carot’icus, an extension of the cavernous sinus into the carotid canal. cavernous 8., a venous sinus extending from the sphenoid fi ure Left-eyed: hav- A base found in mustard: