Adjacent Words

Sinus definitions

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Webster's 1828 Dictionary

SI'NUS, n. [L. a bay.]
1. A bay of the sea; a recess in the shore , or an opening in the land.
2. In anatomy, a cavity in a bone or other part, wider at the bottom than at the entrance.
3. In surgery, a little cavity or sack in which pus is collected; an abscess with only a small orifice.
4. An opening; a hollow.

WordNet (r) 3.0 (2005)

n
1: an abnormal passage leading from a suppurating cavity to the body surface [syn: fistula, sinus]
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, sinus]

Merriam Webster's

noun Etymology: Middle English, from Medieval Latin, from Latin, curve, fold, hollow Date: 15th century cavity, hollow: as a. a narrow elongated tract extending from a focus of suppuration and serving for the discharge of pus b. (1) a cavity in the substance of a bone of the skull that usually communicates with the nostrils and contains air (2) a channel for venous blood (3) a dilatation in a bodily canal or vessel c. a cleft or indentation between adjoining lobes (as of a leaf or corolla)

Britannica Concise

Body cavity or hollow. The paranasal sinuses, which are known commonly simply as the sinuses, are any of four sets of cavities in the bones adjoining the nose: maxillary, the largest, between the eye socket and the palate and upper jaw; frontal, just above and between the eye sockets; ethmoidal, consisting of 3-18 thin-walled cavities between the nasal cavities and the eye sockets; and sphenoidal, behind the nasal cavity. All are absent or small at birth, enlarge gradually until puberty, and then grow rapidly. They affect the sound of the voice and may help to warm inhaled air. Their lining produces mucus, which drains into the nasal cavity. Blockage of their outlets by swelling (from allergy or infection; see sinusitis), polyps, or structural problems hamper breathing through the nose and can lead to serious infection. Severe obstruction may require surgery, which must be done with extreme care to avoid harm to nearby brain structures or the eyes.

Oxford Reference Dictionary

n. 1 a cavity of bone or tissue, esp. in the skull connecting with the nostrils. 2 Med. a fistula esp. to a deep abscess. 3 Bot. the curve between the lobes of a leaf. Etymology: L, = bosom, recess

Webster's 1913 Dictionary

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. 2. A bay of the sea; a recess in the shore. 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. 4. (Med.) A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice. 5. (Bot.) A depression between adjoining lobes. Note: A sinus may be rounded, as in the leaf of the white oak, or acute, as in that of the red maple. 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.

Webster's 1913 Dictionary

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. 2. A bay of the sea; a recess in the shore. 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. 4. (Med.) A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice. 5. (Bot.) A depression between adjoining lobes. Note: A sinus may be rounded, as in the leaf of the white oak, or acute, as in that of the red maple. 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.

Collin's Cobuild Dictionary

(sinuses) Your sinuses are the spaces in the bone behind your nose. I still suffer from catarrh and sinus problems. N-COUNT: usu pl

Soule's Dictionary of English Synonyms

n. [L.] 1. Bay, recess. 2. Hollow, opening, bending, sinuosity. 3. (Surg.) Fistula. 4. (Bot.) Hollow. 5. (Conch.) Groove, cavity.

Moby Thesaurus

alveolation, alveolus, antrum, arc, armpit, basin, bow, bowl, catacaustic, catenary, caustic, cavity, circle, concave, concavity, conchoid, crater, crook, crypt, cup, curl, curve, depression, diacaustic, dip, ellipse, festoon, fold, follicle, funnel chest, hole, hollow, hollow shell, hook, hyperbola, lacuna, lituus, parabola, pit, pocket, punch bowl, scoop, shell, sink, socket, tracery, trough, vug