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]).
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.
In process of changing from laminal denti-alveolar to apical alveolar, but the laminal denti-alveolar is still possible in some environments, and is obligatory after /n, t, d/. See Norwegian phonology
The velarized alveolar lateral approximant (dark l) is a type of consonantal sound used in some 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.
Laminal; pharyngealized in northern accents, velarized or post-palatalised in southern accents. It is an allophone of /l/ before consonants and pauses, and also prevocalically when after the open back vowels /ɔ, ɑ/. Many northern speakers realize the final /l/ as a strongly pharyngealised vocoid [ɤˤ], whereas some Standard Belgian speakers use the clear /l/ in all positions. See Dutch phonology
When [lˠ ~ lʶ ~ lˤ ~ lˀ], most often dental. Coda is now vocalized to [u̯ ~ ʊ̯] in most of Brazil (as in rural parts of Alto Minho and Madeira). Stigmatized realizations such as [ɾ ~ ɽ ~ ɻ], the /ʁ/ range, [j] and even [∅] (zero) are some other coda allophones typical of Brazil. Can be always dental and always dark (especially before back/rounded and close/unrounded vowels) in most dialects. See Portuguese phonology
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