Sinus may refer to:
Anatomy
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Sinus (anatomy), a sac or cavity in any organ or tissue
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Paranasal sinuses, air cavities in the cranial bones, especially those near the nose, including:
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Maxillary sinus, is the largest of the paranasal sinuses, under the eyes, in the maxillary bones
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Frontal sinus, superior to the eyes, in the frontal bone, which forms the hard part of the forehead
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Ethmoid sinus, formed from several discrete air cells within the ethmoid bone between the eyes and under the nose
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Sphenoidal sinus, in the sphenoid bone at the center of the skull base under the pituitary gland
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Anal sinuses, the furrows which separate the columns in the rectum
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Dural venous sinuses
The dural venous sinuses (also called dural sinuses, cerebral sinuses, or cranial sinuses) are venous channels found between the endosteal and meningeal layers of dura mater in the brain. They receive blood from the cerebral veins, receive cereb ...
, venous channels found between layers of dura mater in the brain
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Sinus (botany)
In botany, a sinus is a space or indentation between two lobes or teeth, usually on a leaf. The term is also used in mycology. For example, one of the defining characteristics of North American species in the ''Morchella elata'' clade of morel ...
, a space or indentation, usually on a leaf
Heart
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Sinus node, a structure in the superior part of the right atrium
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Sinus rhythm, normal beating on an ECG
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Coronary sinus, a vein collecting blood from the heart
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Sinus venosus, a cavity in the heart of embryos
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Sinus venarum, a part of the wall of the right atrium in adults, developed from the sinus venosus
Other uses
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Sinus (Chalcidice), a town of ancient Chalcidice, Greece
* ''Sinus'', gulf or bay in Latin, used in numerous toponyms in ancient writing (e.g.,
Sinus Magnus,
Sinus Flanaticus, etc.)
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Sine
In mathematics, sine and cosine are trigonometric functions of an angle. The sine and cosine of an acute angle are defined in the context of a right triangle: for the specified angle, its sine is the ratio of the length of the side that is oppo ...
, a trigonometric math function (Latin ''sinus'')
See also
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Sinus Medii, a small lunar mare
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Sinus Successus, a lunar feature
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Sines
Sines () is a city and a municipality in Portugal. The municipality, divided into two parishes, has around 14,214 inhabitants (2021) in an area of . Sines holds an important oil refinery and several petrochemical industries. It is also a popular ...
, a municipality in Alentejo, Portugal (Latin ''Sinus'')
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Sinusitis, a common ailment resulting in the inflammation of the paranasal sinuses
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