Co-articulated consonants or complex consonants are consonants produced with two simultaneous places of articulation. They may be divided into two classes: doubly articulated consonants with two primary places of articulation of the same manner (both stop, or both nasal, etc.), and consonants with secondary articulation, that is, a second articulation not of the same manner.
|IPA: Co-articulated consonants|
An example of a consonant with secondary articulation is the voiceless labialized velar stop [kʷ] has only a single stop articulation, velar [k], with a simultaneous approximant-like rounding of the lips.
There is a large number of common secondary articulations. The most frequently encountered are labialization (such as [kʷ]), palatalization (such as the Russian "soft" consonants like [pʲ]), velarization (such as the English "dark" el [lˠ]), and pharyngealization (such as the Arabic emphatic consonants like [tˤ]).
As might be expected from the approximant-like nature of secondary articulation, it is not always easy to tell whether a co-articulated approximant consonant such as /w/ is doubly or secondarily articulated. In some English dialects, for example, /w/ is a labialized velar that could be transcribed as [ɰʷ], but the Japanese /w/ is closer to a true labial-velar, [ɰ͡β̞]. It is common usage to restrict the letter ⟨w⟩ to the former.
The glottis controls phonation, and works simultaneously with many consonants. It is not normally considered an articulator, and an ejective such as [kʼ], with simultaneous closure of the velum and glottis, is not normally considered to be a co-articulated consonant.
In phonology, assimilation is a sound change where some phonemes (typically consonants or vowels) change to be more similar to other nearby sounds. It is a common type of phonological process across languages. Assimilation can occur either within a word or between words. It occurs in normal speech, and it becomes more common in more rapid speech. In some cases, assimilation causes sound spoken to differ from the normal "correct" pronunciation of each sound in isolation. In other cases, the changed sound is considered canonical for that word or phrase.
For an English example, "handbag" (canonically ) is often pronounced in rapid speech. This is because the [m] and [b] sounds are both bilabial consonants and their places of articulation are similar; whereas the sequence [d]-[b] has different places but similar manner of articulation (voiced stop) and is sometimes elided, causing the canonical [n] phoneme to sometimes assimilate to [m] before the [b]. The pronunciations or are, however, common in normal speech. By contrast, the word "cupboard", historically a compound of "cup" and "board" , is always pronounced and never *, even in slow, highly articulated speech.
As in these examples, sound segments typically assimilate to a following sound, but they may also assimilate to a preceding one. While assimilation most commonly occurs between immediately adjacent sounds, it may occur between sounds separated by others.Assimilation can be synchronic—that is, an active process in a language at a given point in time—or diachronic—that is, a historical sound change.
A related process is coarticulation, where one segment influences another to produce an allophonic variation, such as vowels becoming nasalized before nasal consonants (/n, m, ŋ/) when the soft palate (velum) opens prematurely or /b/ becoming labialized as in "boot" [bʷuːt̚] or "ball" [bʷɔːɫ] in some accents. This article describes both processes under the term assimilation.Coarticulation
Coarticulation in its general sense refers to a situation in which a conceptually isolated speech sound is influenced by, and becomes more like, a preceding or following speech sound. There are two types of coarticulation: anticipatory coarticulation, when a feature or characteristic of a speech sound is anticipated (assumed) during the production of a preceding speech sound; and carryover or perseverative coarticulation, when the effects of a sound are seen during the production of sound(s) that follow. Many models have been developed to account for coarticulation. They include the look-ahead, articulatory syllable, time-locked, window, coproduction and articulatory phonology models.
Coarticulation in phonetics refers to two different phenomena:
the assimilation of the place of articulation of one speech sound to that of an adjacent speech sound. For example, while the sound /n/ of English normally has an alveolar place of articulation, in the word tenth it is pronounced with a dental place of articulation because the following sound, /θ/, is dental.
the production of a co-articulated consonant, that is, a consonant with two simultaneous places of articulation. An example of such a sound is the voiceless labial-velar plosive /k͡p/ found in many West African languages.The term coarticulation may also refer to the transition from one articulatory gesture to another.Epenthesis
In phonology, epenthesis (; Greek ἐπένθεσις) means the addition of one or more sounds to a word, especially to the interior of a word (at the beginning prothesis and at the end paragoge are commonly used). The word epenthesis comes from epi- "in addition to" and en "in" and thesis "putting". Epenthesis may be divided into two types: excrescence, for the addition of a consonant, and anaptyxis () for the addition of a vowel. The opposite process where one or more sounds are removed is referred to as elision.Labialized velar consonant
A labialized velar or labiovelar is a velar consonant that is labialized, with a /w/-like secondary articulation. Common examples are [kʷ, ɡʷ, xʷ, ŋʷ], which are pronounced like a [k, ɡ, x, ŋ], with rounded lips, such as the labialized voiceless velar plosive [kʷ]. Such sounds occur across Africa and the Americas, in the Caucasus, etc.