sinus

As a noun sinus

is sine (abbreviated form: sin ).

As an adjective sinuslike is

resembling a sinus or some aspect of one.

As nouns the difference between sinus and cefdinir

is that sinus is sine (abbreviated form: sin ) while cefdinir is a semisynthetic broad-spectrum cephalosporin antibiotic, proven effective for common bacterial infections of the ear, sinus, throat, and skin.

In anatomy terms the difference between sinus and sinoatrial

is that sinus is a pouch or cavity in any organ or tissue, especially the paranasal sinus while sinoatrial is relating to the venous sinus and the right atrium of the heart.

As a noun sinus

is a pouch or cavity in any organ or tissue, especially the paranasal sinus.

As an adjective sinoatrial is

relating to the venous sinus and the right atrium of the heart.

As nouns the difference between sinus and polysinusitis

is that sinus is a pouch or cavity in any organ or tissue, especially the paranasal sinus while polysinusitis is the simultaneous inflammation of multiple sinuses.