The labial–palatal approximant can in many cases be considered the semivocalic equivalent of the close front rounded vowel[y]. They alternate with each other in certain languages, such as French, and in the diphthongs of some languages, ⟨ɥ⟩ and ⟨y̑⟩ with the non-syllabic diacritic are used in different transcription systems to represent the same sound. Sometimes,[1] ⟨y̆⟩ is written in place of ⟨y̑⟩, even though the former symbol denotes an extra-short [y] in the official IPA.
Some languages, though, have a palatal approximant that is unspecified for rounding, and therefore cannot be considered the semivocalic equivalent of either [y] or its unrounded counterpart [i]. An example of such a language is Spanish, in which the labialized palatal approximant (not a semivowel) appears allophonically with rounded vowels in words such as ayuda[aˈʝ̞ʷuð̞a] 'help'. According to some sources, it is not correct to transcribe this with the symbol ⟨ɥ⟩, which has a different kind of rounding, or with ⟨jʷ⟩, which implies spread lips; the only suitable transcription is ⟨ʝ̞ʷ⟩.[2] See palatal approximant for more information.
There is also the labialized postpalatal approximant[3] in some languages, which is articulated slightly more back compared with the place of articulation of the prototypical labialized palatal approximant, though not as back as the prototypical labialized velar approximant. It can be considered the semivocalic equivalent of the close central rounded vowel[ʉ]. The International Phonetic Alphabet does not have a separate symbol for that sound, though it can be transcribed as ⟨ɥ̄⟩ or ⟨ɥ˗⟩ (both symbols denote a retracted ⟨ɥ⟩), ⟨ɥ̈⟩ (centralized ⟨ɥ⟩), ⟨w̟⟩ (advanced ⟨w⟩) or ⟨ẅ⟩ (centralized ⟨w⟩). The equivalent X-SAMPA symbols are H_o, H_", w_+ and w_", respectively. Other possible transcriptions include a centralized and labialized ⟨j⟩ (⟨j̈ʷ⟩ in the IPA, j_"_w in X-SAMPA) and a non-syllabic ⟨ʉ⟩ (⟨ʉ̯⟩ in the IPA, }_^ in X-SAMPA).
Especially in broad transcription, the labialized postpalatal approximant may be transcribed as a palatalized and labialized velar approximant (⟨wʲ⟩ in the IPA, w' or w_j in X-SAMPA).
Compressed palatal approximant
The compressed palatal approximant is typically transcribed in IPA simply as ⟨ɥ⟩, and that is the convention used in this article. There is no dedicated diacritic for compression in the IPA. However, the compression of the lips can be shown with the letter ⟨β̞⟩ as ⟨j͡β̞⟩ (simultaneous [j] and labial compression) or ⟨jᵝ⟩ ([j] modified with labial compression). The spread-lip diacritic ⟨ ͍ ⟩ may also be used with a labialized approximant letter ⟨ɥ͍⟩ as an ad hoc symbol, though technically 'spread' means unrounded.
The compressed post-palatal approximant[3] can be transcribed simply as ⟨ɥ̈⟩ (centralized [ɥ]), and that is the convention used in this article. Other possible transcriptions include ⟨j̈ᵝ⟩ (centralized [j] modified with labial compression) and ⟨ɥ͍̈⟩ (centralized [ɥ] with the spread-lip diacritic).
Because the labialized palatal approximant is assumed to have compression, and few descriptions cover the distinction, some examples in the table below may actually have protrusion.
Non-syllabic element of the common diphthongal realization of /ʉː/ ([ʉ̟ɥ]); can be a fricative instead. Palatal in the Central Standard variety, post-palatal in some other varieties. See Swedish phonology
As there are no diacritics in the IPA to distinguish protruded and compressed rounding, an old diacritic for labialization, ⟨ ̫⟩, will be used here as an ad hoc symbol for the protruded palatal approximant. Another possible transcription is ⟨ɥʷ⟩ or ⟨jʷ⟩ (a palatal approximant modified by endolabialization).
Acoustically, this sound is "between" the more typical compressed palatal approximant [ɥ] and the non-labialized palatal approximant [j].
^ abInstead of "post-palatal", it can be called "retracted palatal", "backed palatal", "palato-velar", "pre-velar", "advanced velar", "fronted velar" or "front-velar". For simplicity, this article uses only the term "post-palatal".
Chirkova, Katia; Chen, Yiya (2013), "Xumi, Part 1: Lower Xumi, the Variety of the Lower and Middle Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 363–379, doi:10.1017/S0025100313000157
Chirkova, Katia; Chen, Yiya; Kocjančič Antolík, Tanja (2013), "Xumi, Part 2: Upper Xumi, the Variety of the Upper Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 381–396, doi:10.1017/S0025100313000169
Valenzuela, Pilar M.; Márquez Pinedo, Luis; Maddieson, Ian (2001), "Shipibo", Journal of the International Phonetic Association, 31 (2): 281–285, doi:10.1017/S0025100301002109