Bilabial trill
The
bilabial trill is a type of
consonantal sound, used in some
spoken languages. The symbol in the
International Phonetic Alphabet that represents this sound is , and the equivalent
X-SAMPA symbol is
B\.
Features of the bilabial trill:
* Its
manner of articulation is
trill, which means it is produced by vibrations of the articulators. In most instances, it is only found as the trilled release of a
prenasalized stop.
* Its
place of articulation is
bilabial which means it is articulated with both
lips.
* Its
phonation type is voiced, which means the vocal cords are vibrating during the articulation.
* It is an
oral consonant, which means air is allowed to escape through the mouth.
* It is a
central consonant, which means it is produced by allowing the airstream to flow over the middle of the tongue, rather than the sides.
* The
airstream mechanism is
pulmonic egressive, which means it is articulated by pushing air out of the
lungs and through the vocal tract, rather than from the
glottis or the mouth.
English does not have a bilabial trill in any words. It does however use a rather loose bilabial trill to express that one is shivering cold, which is spelled
brrr.
The bilabial trill exists as a phoneme in a few languages. In most of the languages where it occurs, it occurs only as a prenasalised bilabial stop with trilled release, . This developed historically from a prenasalized stop before a relatively high
back vowel, such as , in all but a couple languages, and are usually still limited to such environments. An example is the
Kele word "its fruit". The known exceptions to this pattern are in
Nias and the occasionally trilled fricative vowels of
Yi.
Some languages, such as
Mangbetu (spoken in North-Eastern
Zaire) and
Mewun (spoken in
Vanuatu), may have both
voiced and
voiceless bilabial trill.
Amuzg has the bilabial trill, but uses it only exceptionally.
Baka (spoken in
Vanuatu) has the bilabial trill, but it is used rarely.
In
Abkhaz and
Ubykh, the "affricates" are
allophones of .
In Pirahã, the bilabial trill is an allophone of /b/.
Liangshang (Cool Mountain) Yi has two "buzzed" or fricative vowels, written ṳ, i̤, which may also be trilled, .
*
Linguist List posting about languages that have bilabial trill*
Voiceless dental bilabially trilled affricate*
List of phonetics topics
