Found 2 items, similar to sinus.
English → English (WordNet) Definition: sinus sinus n 1: an abnormal passage leading from a suppurating cavity to the body surface [syn: fistula] 2: any of various air-filled cavities especially in the bones of the skull 3: a wide channel containing blood; does not have the coating of an ordinary blood vessel [syn: venous sinus]
English → English (gcide) Definition: Sinus Sinus \Si"nus\, n.; pl. L. Sinus, E. Sinuses. [L., a bent surface, a curve, the folds or bosom of a garment, etc., a bay. Cf. Sine, n.] 1. An opening; a hollow; a bending. [1913 Webster] 2. A bay of the sea; a recess in the shore. [1913 Webster] 3. (Anat. & Zo["o]l.) A cavity; a depression. Specifically: (a) A cavity in a bone or other part, either closed or with a narrow opening. (b) A dilated vessel or canal. [1913 Webster] 4. (Med.) A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice. [1913 Webster] 5. (Bot.) A depression between adjoining lobes. [1913 Webster] Note: A sinus may be rounded, as in the leaf of the white oak, or acute, as in that of the red maple. [1913 Webster] Pallial sinus. (Zo["o]l.) See under Pallial. Sinus venosus. [L., venous dilatation.] (Anat.) (a) The main part of the cavity of the right auricle of the heart in the higher vertebrates. (b) In the lower vertebrates, a distinct chamber of the heart formed by the union of the large systematic veins and opening into the auricle. [1913 Webster] Sinus \Si"nus\, n.; pl. L. Sinus, E. Sinuses. [L., a bent surface, a curve, the folds or bosom of a garment, etc., a bay. Cf. Sine, n.] 1. An opening; a hollow; a bending. [1913 Webster] 2. A bay of the sea; a recess in the shore. [1913 Webster] 3. (Anat. & Zo["o]l.) A cavity; a depression. Specifically: (a) A cavity in a bone or other part, either closed or with a narrow opening. (b) A dilated vessel or canal. [1913 Webster] 4. (Med.) A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice. [1913 Webster] 5. (Bot.) A depression between adjoining lobes. [1913 Webster] Note: A sinus may be rounded, as in the leaf of the white oak, or acute, as in that of the red maple. [1913 Webster] Pallial sinus. (Zo["o]l.) See under Pallial. Sinus venosus. [L., venous dilatation.] (Anat.) (a) The main part of the cavity of the right auricle of the heart in the higher vertebrates. (b) In the lower vertebrates, a distinct chamber of the heart formed by the union of the large systematic veins and opening into the auricle. [1913 Webster]