Nasalization in phonetics

Nasalization in phonetics

In linguistics, the imparting of a nasal quality to a sound, by opening up the nasal cavity as an extra resonator. All speech sounds are made with some configuration of the throat and oral cavity. The velum or soft palate acts as a drawbridge: it is normally retracted so as to close off the nasal cavity, but in nasal sounds it is lowered to allow air to resonate simultaneously through the nose.

Nasal consonants, like M and N and the Ng in sing and the Ñ in España, have a complete closure somewhere in the mouth, and air escapes only through the nose. They may also be called nasal stops.

Nasal vowels have both the oral and nasal cavities open. Nasalization is thus an extra articulation on an oral vowel, so nasal vowels may also be called nasalized vowels. This is nitpicking, but there are no solely nasal sounds. Also, configuration of the nasal cavity can't be altered (say by flaring the nostrils), or at least if this is physically possible it's never been reported as used in any language. The only parameter of nasality is whether the velum is open or shut.

Familiar languages with nasal vowels are French, Portuguese, Polish, and Hindi, and they are quite common world-wide, especially in West African languages. The four French vowels are illustrated by
 the phrase un bon vin blanc 'a good white wine'. All languages without exception have oral vowels, and usually have more oral than nasal.

The IPA phonetic symbol for nasalization is a tilde, thus [œ˜ bõ vE˜ blã]. (Only the Portuguese letters ã õ will show up correctly in HTML, so I've had to use a separate tilde: it should be over the vowel in all cases.) In Polish Lech Wałęsa = [lex va'we˜sa]

This is called primary nasalization when the language systematically uses nasal vowels as distinct phonemes: French [bõ] 'good' contrasts with [bo] 'beautiful'.

Most consonants can't be nasalized, or rather a nasalized B just is an M. They are the same orally, and instead of exploding abruptly as B does, the air is released continuously through the nose in M. But some consonants, those called sonorants, allow their normal oral articulation to have simultaneous nasality imposed over them. This set includes the laterals or L-like sounds, the rhotics or R-like sounds, and the approximants including W and Y. However, it is extremely rare to have nasalized sonorants as phonemes: usually they are the result of secondary nasalization.