The alveolar lateral approximant is a type of consonantal sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents dental, alveolar, and postalveolar lateral approximants is ⟨l⟩, and the equivalent X-SAMPA symbol is l.
As a sonorant, lateral approximants are nearly always voiced. Voiceless lateral approximants, /l̥/ are common in Sino-Tibetan languages, but uncommon elsewhere. In such cases, voicing typically starts about halfway through the hold of the consonant. No language is known to contrast such a sound with a voiceless alveolar lateral fricative [ɬ].
In a number of languages, including most varieties of English, the phoneme /l/ becomes velarized in certain contexts, a sound often called "dark l". Some languages, like many North American dialects of English, may not have a "clear" /l/ at all, or use it only before front vowels (especially [i]).
Features of the voiced alveolar lateral approximant:
Its manner of articulation is approximant, which means it is produced by narrowing the vocal tract at the place of articulation, but not enough to produce a turbulent airstream.
There are four specific variants of [l]:
Dental, which means it is articulated with either the tip or the blade of the tongue at the upper teeth, termed respectively apical and laminal.
Denti-alveolar, which means it is articulated with the blade of the tongue at the alveolar ridge, and the tip of the tongue behind upper teeth.
Alveolar, which means it is articulated with either the tip or the blade of the tongue at the alveolar ridge, termed respectively apical and laminal.
Postalveolar, which means it is articulated with either the tip or the blade of the tongue behind the alveolar ridge, termed respectively apical and laminal.
Its phonation is voiced, which means the vocal cords vibrate during the articulation.
It is an oral consonant, which means air is allowed to escape through the mouth only.
It is a lateral consonant, which means it is produced by directing the airstream over the sides of the tongue, rather than down the middle.
The airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the lungs and diaphragm, as in most sounds.
Languages may have clear apical or laminal alveolars, laminal denti-alveolars (such as French), or true dentals, which are uncommon. However, a true dental generally occurs allophonically before /θ/ in languages that have it, as in English health.
The velarized alveolar lateral approximant (dark l) is a type of consonantal sound used in some spoken languages. It is an alveolar, denti-alveolar, or dental lateral approximant, with a secondary articulation of velarization or pharyngealization. The regular symbols in the International Phonetic Alphabet that represent this sound are ⟨lˠ⟩ (for a velarized lateral) and ⟨lˤ⟩ (for a pharyngealized lateral), though the dedicated letter ⟨ɫ⟩, which covers both velarization and pharyngealization, is perhaps more common. The last symbol should never be confused with ⟨ɬ⟩, which represents the voiceless alveolar lateral fricative. However, some scholars use that symbol to represent the velarized alveolar lateral approximant anyway - such usage is considered non-standard.
If the sound is dental or denti-alveolar, one could use a dental diacritic to indicate so: ⟨l̪ˠ⟩, ⟨l̪ˤ⟩, ⟨ɫ̪⟩.
Velarization and pharyngealization are generally associated with more dental articulations of coronal consonants so dark l tends to be dental or denti-alveolar while clear l tends to be retracted to an alveolar position.
Features of the dark l:
Its manner of articulation is approximant, which means it is produced by narrowing the vocal tract at the place of articulation, but not enough to produce a turbulent airstream.
There are four specific variants of [ɫ]:
Dental, which means it is articulated with either the tip or the blade of the tongue at the upper teeth.
Denti-alveolar, which means it is articulated with the blade of the tongue at the alveolar ridge, and the tip of the tongue behind upper teeth.
Alveolar, which means it is articulated with either the tip or, more rarely, the blade of the tongue at the alveolar ridge, termed respectively apical and laminal.
Postalveolar, which means it is articulated with either the tip or the blade of the tongue behind the alveolar ridge, termed respectively apical and laminal.
It has a secondary articulation of velarization or pharyngealization, meaning that the back or root of the tongue approaches the soft palate (velum), or the back of the throat, respectively.
Its phonation is voiced, which means the vocal cords vibrate during the articulation.
It is an oral consonant, which means air is allowed to escape through the mouth only.
It is a lateral consonant, which means it is produced by directing the airstream over the sides of the tongue, rather than down the middle.
The airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the lungs and diaphragm, as in most sounds.
