Phonetics

A nasal consonant is one in which the air escapes only through the nose. For this to happen, two articulatory actions are necessary: firstly, the soft palate (or velum) must be lowered to allow air to escape past it, and secondly, a closure must be made in the oral cavity to prevent air from escaping through it. The closure may be at any place of articulation from bilabial at the front of the oral cavity to uvular at the back (in the latter case there is contact between the tip of the lowered soft palate and the raised back of the tongue). A closure any further back than this would prevent air from getting into the nasal cavity, so a pharyngeal or glottal nasal is a physical impossibility.