Back vowel

A back vowel is any in a class of vowel sound used in spoken languages. The defining characteristic of a back vowel is that the tongue is positioned as far back as possible in the mouth without creating a constriction that would be classified as a consonant. Back vowels are sometimes also called dark vowels because they are perceived as sounding darker than the front vowels.

Near-back vowels are essentially a type of back vowels; no language is known to contrast back and near-back vowels based on backness alone.

In their articulation, back vowels do not form a single category, but may be either raised vowels such as [u] or retracted vowels such as [ɑ].

Unrounded back vowels are typically centralized, that is, near-back in their articulation. This is one reason they are written to the left of rounded back vowels in the IPA vowel chart.

The back vowels that have dedicated symbols in the International Phonetic Alphabet are:

There also are back vowels that don't have dedicated symbols in the IPA:

As here, other back vowels can be transcribed with diacritics of relative articulation applied to letters for neighboring vowels, such as ⟨u̞⟩, ⟨o̝⟩ or ⟨ʊ̟⟩ for a near-close back rounded vowel.

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