nostril n : either one of the two external openings to the nasal cavity in the nose [syn: anterior naris]

English

Etymology

From nose + thirl.

Pronunciation

• , /ˈnɒstrɪl/, /ˈnɒstrəl/, /"nQstrIl/, /"nQstr@l/

Noun

1. Either of the two orifices located on the nose (or on the beak of a bird); used as a passage for air and other gases to travel the nasal passages.

Synonyms

• naris
• nosehole

Translations

References

A nostril (or naris, pl. nares) is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation. Fish do not breathe through their noses, but they do have two small holes used for smelling which may be called nostrils.

The Procellariiformes are distinguished from other birds by having tubular extensions of their nostrils.

In humans, the nasal cycle is the normal ultradian cycle of each nostril's blood vessels becoming engorged in swelling, then shrinking. During the course of a day, they will switch over approximately every four hours or so, meaning that only one nostril is used at any one time.

References

See Also

• Dilator naris muscle

External links

air duct, air hole, air passage, air shaft, air tube, airway, antlia, beak, beezer, bill, blowhole, breathing hole, bugle, conk, louver, louverwork, muffle, muzzle, nares, naris, neb, nib, nose, nostrils, nozzle, olfactories, olfactory area, olfactory cell, olfactory nerves, olfactory organ, olfactory pit, pecker, proboscis, rhinarium, rostrum, schnozzle, shaft, smeller, snoot, snout, spilehole, spiracle, touchhole, transom, trunk, vent, ventage, venthole, ventiduct, ventilating shaft, ventilator, wind tunnel