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.
An example of a doubly articulated consonant is the voiceless labialâÂÂvelar stop , which is pronounced simultaneously at the velum (a ) and at the lips (a ).
In practically all languages of the world that have doubly articulated consonants, these are either clicks or labialâÂÂvelars.
An example of a consonant with secondary articulation is the voiceless labialized velar stop , which has only a single stop articulation, velar , with a simultaneous approximant-like rounding of the lips.
There is a large number of common secondary articulations. The most frequently encountered are:
As might be expected from the approximant-like nature of secondary articulation, it is not always easy to tell whether a co-articulated approximant such as is doubly or secondarily articulated. In some English dialects, for example, is a labialized velar that could be transcribed as .
The glottis controls phonation, and works simultaneously with many consonants. It is not normally considered an articulator, and an ejective such as , with simultaneous closure of the velum and glottis, is not normally considered to be a co-articulated consonant.