A nasal consonant is produced when the velum—that fleshy part of the palate near the back—is lowered, allowing air to escape freely through the nose. The oral cavity still acts as a resonance chamber for the sound, but the air does not escape through the mouth as it is blocked by the tongue. Thus, it is not the nose itself that differentiates between the nasals, but rather the tongue's articulation. Air escapes through both the mouth and the nose during the prodution of a nasal vowel.
Nasal consonants are sonorants, (as are laterals, approximants, and vowels), meaning they do not restrict the escape of the air. (Compare with stop consonants, which block off the air completely, and fricatives, which force the air through a narrow channel. Both stops and fricatives are known as obstruents.) Nasals are sometimes called nasal stops because the flow of air through the mouth is stopped completely, although since air escapes through the nose, the flow is air is not stopped completely.
Acoustically, nasals have bands of energy at around 200 and 2,000 Hz.
List of nasal consonants:
Examples of languages containing nasals:
English, German and Cantonese have [m], [n] and [ŋ]
French has [m], [n] and [ɲ], as well as [ŋ] in a few recent loanwords (such as le parking).
Catalan and Italian have [m], [n], [ɲ] as phonemes, and [ŋ] as an allophone.
Spanish has [m], [n], [ɲ] as phonemes, and [ɱ] and [ŋ] as allophones.
Mohawk has only one nasal phoneme /n/, and Rotokas, a language of Papua New Guinea, has none (although nasals do show up allophonically in that language).
French, Portuguese, and Polish have nasal vowels. In IPA, nasal vowels are indicated by placing a tilde (~) over the vowel in question. So French sang = [sɑ̃].
See also
