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Decreasing the width or diameter of some space or channel, e.g., narrowing of the size of the coronary arteries, usually due to some pathological process.


National Aeronautics and Space Administration.


(nā′zăl) [L. nasus, nose] 1. Pert. to the nose. 2. Uttered through the nose. 3. A nasal bone.

nasal flaring

Intermittent outward movement of the nostrils with each inspiratory effort; indicates an increase in the work of breathing.

nasal gavage

SEE: enteral tube feeding.

nasal meatus

SEE: under meatus.

nasal septum

SEE: nasal septum.

nasal tip

The inferior third of the nose.

nasal trumpet

Nasopharyngeal airway.

nasal width

The maximum width of the nasal aperture.


(năs′ĕnt; nā′sĕnt) [L. nascens, born] 1. Just born; incipient or beginning. 2. Pert. to a substance being set free from a compound.

nasendoscopy, nasoendoscopy

(nāz″en-dos′kŏ-pĕ, nā″zō-en-dos′kŏ-pĕ) [nas(o)- + endoscopy] Inspection of the nose, sinuses, pharynx, and larynx with a small angled endoscope inserted into a nostril.


(nāz″en′dŏ-skōp″), n. nasoendoscope (nā″zō-en′dŏ-skōp″), n.


(nā′zē-on″) [L. nasus, nose + Gr. -ion, a diminutive suffix] The point at which the median anteroposterior plane cuts across the nasofrontal suture.


[L. nasus, nose] Prefix meaning-nose. SEE: rhino-.


(nā″zō-bil′ē-er″ē) [naso- + biliary] Pert. to the nasal passages and the gallbladder, as when a catheter is inserted through the nose and enters the common bile duct via the upper gastrointestinal tract.


(nā″zō-sil′ē-er-ē) [naso- + ciliary (2)] 1. Pert. to the nose, eyebrows, and eyes 2. Pert. to the nerves supplying the nose, eyebrows, and eyes.

nasoduodenal tube

(nā″zō-dū-ă-dē′năl,-doo, nā″zō-dū-ŏd′ĕ-năl,-doo) A flexible tube of silicone or a similar synthetic material, inserted through the nose into the duodenum for short-term enteral feeding. The small weight on the distal end of the tube moves the tube into place through the stomach into the duodenum. Aspiration is less likely than with a nasogastric tube.


(nā″zō-frŏnt′ăl) [naso- + frontal (2)] Pert. to nasal and frontal bones.


(nā″zō-găs′trĭk) [″ + Gr. gaster, belly] Pert. to the nasal passages and ...

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