Labialization

Labialization is a secondary articulatory feature of sounds in some languages. Labialized sounds involve the lips while the remainder of the oral cavity produces another sound. The term is normally restricted to consonants. When vowels involve the lips, they are called rounded.Symbols to the right in a cell are voiced, to the left are voiceless. Shaded areas denote articulations judged impossible.Vowels beside dots are: unrounded • rounded Labialization is a secondary articulatory feature of sounds in some languages. Labialized sounds involve the lips while the remainder of the oral cavity produces another sound. The term is normally restricted to consonants. When vowels involve the lips, they are called rounded. The most common labialized consonants are labialized velars. Most other labialized sounds also have simultaneous velarization, and the process may then be more precisely called labio-velarization. In phonology, labialization may also refer to a type of assimilation process. Labialization is the most widespread secondary articulation in the world's languages. It is phonemically contrastive in Northwest Caucasian (e.g. Adyghe), Athabaskan, and Salishan language families, among others. This contrast is reconstructed also for Proto-Indo-European, the common ancestor of the Indo-European languages; and it survives in Latin and some Romance languages. American English has three degrees of labialization: tight rounded (/w/, initial /r/), slight rounded (/ʃ/, /ʒ/, /tʃ/, /dʒ/, coloring /r/), and unrounded, which in vowels is sometimes called 'spread'. These secondary articulations are not universal. For example, French shares the English slight rounding of /ʃ/, /ʒ/ while Russian does not have slight rounding in its postalveolar fricatives (/ʂ ʐ ɕ ʑ/). A few languages, including Arrernte and Mba, have contrastive labialized forms for almost all of their consonants. Out of 706 language inventories surveyed by Ruhlen (1976), labialization occurred most often with velar (42%) and uvular (15%) segments and least often with dental and alveolar segments. With non-dorsal consonants, labialization may include velarization as well. Labialization is not restricted to lip-rounding. The following articulations have either been described as labialization, or been found as allophonic realizations of prototypical labialization: Eastern Arrernte has labialization at all places and manners of articulation; this derives historically from adjacent rounded vowels, as is also the case of the Northwest Caucasian languages. Marshallese also has labialization at all places of articulation except for coronal obstruents. In North America, languages from a number of families have sounds that sound labialized (and vowels that sound rounded) without participation of the lips. See Tillamook language for an example.