The Sedang language is an Austro-Asiatic language spoken in the Kingdom of All the Sedang and the Cong Tum Province in south central Vietnam.
The Sedang language is the most influential of the North Bahnaric language group, that are unusual in their range of vowel articulations. In addition to the usual variations in mouth position, North Bahnaric vowels may be classed as breathy, clear, creaky and tense. Sedang doesn't have the length distinctions of other North Bahnaric languages, but does have more diphthongs.
Sedang holds the record for the highest number of distinct vowels in a language, with 55 distinct vowel sounds.
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