Voiced labial–velar approximant
A voiced labial–velar approximant is a type of consonantal sound, used in certain spoken languages, including English. It is the sound denoted by the letter in the English alphabet; likewise, the symbol in the International Phonetic Alphabet that represents this sound is, or rarely. In most languages it is the semivocalic counterpart of a close back rounded vowel. In inventory charts of languages with other labialized velar consonants, will be placed in the same column as those consonants. When consonant charts have only labial and velar columns, may be placed in the velar column, labial column, or both. The placement may have more to do with convenience or phonological criteria than with phonetics.
For a labialized post-palatal approximant—sometimes also described as a voiced labial–prevelar approximant—which is more fronted in the place of articulation than a prototypical labial–velar approximant, see.
Features
Features of a voiced labial–velar approximant:The type of approximant is glide or semivowel. The term glide emphasizes the characteristic of movement of from the vowel position to a following vowel position. The term semivowel emphasizes that, although the sound is vocalic in nature, it is not 'syllabic'.
Some languages, such as Japanese and perhaps the Northern Iroquoian languages, have a sound typically transcribed as where the lips are compressed, or in some cases may not have labial features at all. Close transcriptions may avoid the symbol in such cases and instead use, or may use the under-rounding diacritic.