Nares

n. nostrils

n. nostril, nasal passage (Anatomy)

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.
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Nares /na·res/ [L.] the nostrils; the external openings of the nasal cavity. nares [L.] plural of naris; the openings of the nasal cavity. [more]Nares - Community and Resources

Noun
1. any of the openings to the nasal cavities that allow air to flow through the cavities to the pharynx
(hypernym) orifice, opening, porta
(hyponym) nostril, anterior naris

(n. pl.)
The nostrils or nasal openings, -- the anterior nares being the external or proper nostrils, and the posterior nares, the openings of the nasal cavities into the mouth or pharynx.