Caucasian languages, historical * has also become palatalized, becoming in Ubykh and in most Circassian varieties. In both regions the languages retain a labialized velar series (e.g. in the Pacific Northwest) as well as uvular consonants. In the languages of those families that retain plain velars, both the plain and labialized velars are pre-velar, perhaps to make them more distinct from the uvulars which may be post-velar. Prevelar consonants are susceptible to palatalization. A similar system, contrasting with and leaving marginal at best, is reconstructed for Proto-Indo-European. Apart from the voiced stop , no other velar consonant is particularly common, even the and that occur in English. Of course, there can be no phoneme in a language that lacks voiced stops, like Mandarin Chinese, but it is sporadically missing elsewhere. Of the languages surveyed in the World Atlas of Language Structures, about 10% of languages that otherwise have are missing . Pirahã has both a and a phonetically. However, the does not behave as other consonants, and the argument has been made that it is phonemically , leaving Pirahã with only as an underlyingly velar consonant. Hawaiian does not distinguish from ; tends toward at the beginning of utterances, before , and is variable elsewhere, especially in the dialect of Niihau and Kauai. Since Hawaiian has no , and varies between and , it is not clearly meaningful to say that Hawaiian has phonemic velar consonants. Several Khoisan languages have limited numbers or distributions of pulmonic velar consonants. (Their click consonants are articulated in the uvular or possibly velar region, but that occlusion is part of the airstream mechanism rather than the place of articulation of the consonant.) Khoekhoe, for example, does not allow velars in medial or final position, but in Juǀ'hoan velars are rare even in initial position. consonants Normal velar consonants are dorso-velar: The dorsum (body) of the tongue rises to contact the velum (soft palate) of the roof of the mouth. In disordered speech there are also velo-dorsal stops, with the opposite articulation: The velum lowers to contact the tongue, which remains static. In the extensions to the IPA for disordered speech, these are transcribed by reversing the IPA letter for a velar consonant, e.g. ⟨⟩ for a voiceless velodorsal stop, ⟨⟩ for voiced, and ⟨⟩ for nasal. See also Velarization Place of articulation List of phonetics topics Notes References Further reading Place of articulation