|Manners of articulation|
In phonetics and phonology, a sonorant is a speech sound that is produced with continuous, non-turbulent airflow in the vocal tract; these are the manners of articulation that are most often voiced in the world's languages. Vowels are sonorants, as are consonants like /m/ and /l/: approximants, nasals, taps, and trills. In the sonority hierarchy, all sounds higher than fricatives are sonorants. They can therefore form the nucleus of a syllable in languages that place that distinction at that level of sonority; see Syllable for details.
The word resonant is sometimes used for these non-turbulent sounds. In this case, the word sonorant may be restricted to non-vocoid resonants; that is, all of the above except vowels and semivowels. However, this usage is becoming dated.
Sonorants contrast with obstruents, which do stop or cause turbulence in the airflow. They include fricatives and stops (for example, /s/ and /t/). Among consonants pronounced in the back in the mouth or in the throat (uvulars, pharyngeals, and glottals), the distinction between an approximant and a voiced fricative is so blurred that no language is known to contrast them.
A typical sonorant inventory found in many languages comprises the following: two nasals /m/, /n/, two semivowels /w/, /j/, and two liquids /l/, /r/. English has the following sonorant consonantal phonemes: /l/, /m/, /n/, /ŋ/, /ɹ/, /w/, /j/.
Whereas most obstruents are voiceless, the great majority of sonorants are voiced. It is certainly possible to make voiceless sonorants, but they occur as phonemic in only about 5 percent of the world's languages. These are almost exclusively found in the area around the Pacific Ocean in Oceania, East Asia, and North and South America, and belong to a number of language families, among them Austronesian, Sino-Tibetan, Na-Dene and Eskimo–Aleut. An example from a different part of the world is Welsh, which contains a phonemic voiceless alveolar trill /r̥/. In every case where a voiceless sonorant does occur, there is a contrasting voiced sonorant (i.e. whenever a language contains a phoneme such as /r̥/, it also contains a corresponding voiced phoneme, /r/ in this case).
Voiceless sonorants tend to be extremely quiet and very difficult to recognise even for those people whose language does contain them. They have a strong tendency to either revoice or undergo fortition, for example to form a fricative like /ç/ or /ɬ/.